Flags

Flags
2-7 players

flags-3pFlags is a simple game which adds training elements to a throw around. It will expose your weaknesses and challenge your strengths. Set out two markers (water bottles are good) a few yards apart, one directly downwind of the other – these mark the goal line – the windier it is, the longer the goal line should be. The higher the skill of the players (and/or the lesser the wind), the narrower the goal line.

2 players: Throw from where you catch, don’t cut for throws but do move to catch them. (1) Throw over the goal line at any height, (2) Throw around the far side of the goal [OI], (3) Throw around the inside of the goal [IO]

3 players: 2v1 – Rolling defender, cutting now encouraged. All players can move freely and pass on either side of the flags, but only passes across the goal line (at any height) count as goals. Goals reset a shot clock to prevent stalling, and the shot clock can be counted by the defender from anywhere on the field.

Felix, Will and Edgars play 3-player Flags.
3v2 / 4v3: More players can be brought in both on offence and defence, and the goal widened.

Experiment with different goal sizes, goal orientation to the wind, restricting the surrounding space with back lines, and so on. I recommend stalling from 4-10, as this is most game-like – mimicking the common situation where a thrower looks for a secondary option at stall 3. Let me know if you come up with some interesting rules or modifications yourself! As it was written on the back of the first frisbee – Play catch. Invent games. Have fun.

Intuitive v Analytic players

I was just reading an article from 2015 on Skyd about Intuitive vs. Analytical Thinking in Ultimate [link], where the author (Alex Davis) places players in two categories;

The Intuitive is everybody’s favourite kind of athlete. Team sports culture celebrates intuition, and true geniuses of the archetype attract lofty accolades: they have “natural athleticism,” “potential,” and “strong instincts,” as if their qualities stemmed from some unknowable magic. They defy more concrete description because–frankly–they simply don’t work according to concrete, well-articulated methods. They feel their way through the game, often without explanation. Quick-thinking and coordinated, the Intuitives perceive the playing field according to shades of instinct, reflex, and experiential knowledge. In team sports in general–and ultimate in particular–we eagerly recruit for this seemingly unteachable intuition, and we then try to equip it with sport-specific tools and skills.

On the opposite end of the spectrum dwell those I’ll call the Analysts. Characteristically methodical, deliberate, and hard-working creatures, they think in firm, defined terms. They value correctness over quickness. They fight temptations and external pressures. They thrive on well-defined frameworks, rules, and mechanisms, informed by their accumulated experience. What they may lack in spontaneity or instinct, they usually make up for with sheer effort. Unlike the Intuitives, their mindset demands a degree of explanation, detail, and investment that coaches often struggle to satisfy.

As an Intuitive-player-turned-coach, I  have found the process of learning how to teach others to be very enlightening for all areas of my game. Analysing my intuition-led on-field actions in depth led me to a greater understanding of those actions, which has made passing on that knowledge / understanding possible & successful.

coachy-cliopboard

Not making notes of which players are Analysts and which are Intuitive

For example, slow fakes with the disc – they feel good and are fun to do, but when I look deeper I realise they serve many purposes – a slow fake has the status of potentially being a throw for a long time, meaning downfield defenders must commit and stay committed to stopping a throw which could come at any point, which makes them more likely to either over-commit or to bite on the wrist snap at the end. If the defender isn’t watching then a slow fake (or slow wind-up) opens a communication channel with the receiver and gets them on the same page as the thrower, in sync and able to cut for the throw or react immediately to the fake as appropriate. Until I stop and think about the nuances, slow fakes are simply approved of and encouraged by the pattern recognition area of my brain, and become part of my style.

Saying ‘I’m not sure why this works’ or ‘Do this because it feels right’ is better than guessing at a reason and then teaching it as fact, but true understanding should be sought by all coaches, and comes from analysis. Intuitives and Analysts working together make great coaching teams, providing they can communicate. Gaining deeper understanding has helped to guide my intuition further, including giving me the knowledge of when to control it for the benefit of the team, and strengthens me as a player year upon year. Once the analysis of a technique such as slow fakes has been done, I am more able to consciously recognise situations where I can suck defenders in or open communication channels with cutters, and construct mental models of the play beyond just that fake or throw.

pointing-diff-directions

Pointing in different directions – Analyst vs Intuitive?

There are a few players who I struggle to connect fully with as a coach, who I now realise are on the Analyst end of the spectrum, and I put the lack of connection down to the relatively unexplored nature of some of what I have been trying to teach. When trying to convince players to change the way they approach the vast arenas of offence or defence, the lack of a clear positive example (such as an elite team winning a championship with what I’m trying to teach) immediately makes everybody sceptical. When teaching particular throwing technique – such as getting a player to shift focus to spin rather than power in order to increase the distance of their throws – the results of the change are often immediate and clear, so any initial scepticism can be quickly either upheld or discarded. When teaching an offence or defence as a whole, the plethora of nuances involved and the ambiguity in evaluating the results (a turnover or a score happens, but what were the real causes?), means that Analysts possibly struggle to build a complete working mental model of the systems – requiring all sorts of assumptions, and it doesn’t make sense to them to take the ‘leap of faith’ needed to cross the unexplored areas & onto the unproven ground.

Intuitive-types will ‘feel’ positive (or negative) results of offensive or defensive changes almost immediately – they can sense the improvement of their team’s game regardless of scores or turnovers, and be keen to explore the ideas further in order to perpetuate these positive feelings (or vice-versa). They do not need full understanding, trust in a coach, or ‘proof’, as their evaluation is not related to a fully working mental model, tangible results, or the experiences of others.

fieldwithlines

A non-flow offence with potential flow moves drawn on by Frank

For example – when attempting to convey the merits of initiating flow – a player has a choice between taking an immediate yard-losing open pass, or looking downfield for a few seconds. Regardless of which option they take, it’s unlikely they will turn over immediately, and either one could fairly quickly result in a score. The immediate shot to the end zone for the goal is the quickest validation, but for flow fans that would be a false positive. If they take the open pass, it’s possible the disc will continue moving and then turn over a few passes later without even an attempt to score or break the force – but the opposite outcome for all these situations is also possible, as it is dependant upon a huge variety of other factors (including the defence). Given the difficulty of analysing the merits of either approach with any level of clarity or certainty, it’s natural for Analytic players to look at championship-winning teams for an idea of which approach is ‘correct’, whereas Intuitive players prefer to experiment with either approach and judge which one ‘feels’ right to them – being far less concerned with attempting to analyse the outcomes (immune to false positives), not depending on trust in their coach, and not desiring to look to the championship-winning teams for guidance.

felix-pp-reacharound2

Analyze This

Intuition is relied upon over analysis whilst a new strategy / tactic / technique is being played and developed, as it guides the direction of development through uncharted territory using the powerful pattern-recognition ability of humans. However, intuition is not perfect and can be very much a trial-and-error process, so whilst a strategy is in its development stage the coach cannot (and should not attempt to) fully explain it – which can come across as weakness or uncertainty, and is an unsatisfactory way of training for Analysts. It therefore makes sense that the status quo is usually perpetuated, and it takes a long time for overarching strategic changes to be adopted. Only after a strategy has matured is it possible to develop a full understanding of it, and therefore be in a position to convey this understanding in a way that satisfies both Analytic and Intuitive players alike at trainings.

It’s quite possible that the majority of those who decide whether or not to implement strategies – team leaders, training organisers, coaches – are Analysts, whilst Intuitive-types simply focus on playing the game and are generally less inclined to coaching or leadership roles (although if their talent stands out, they are often put into these positions and begin by leading by example). It’s also possible the status-quo strategies drive away some talented Intuitive-types to other sports which ‘feel’ better to them – where they’re not asked to stack up / focus solely on their mark, or enforce other traditional Ultimate tactics which feel counter-intuitive and are unseen in other team sports. The athletes I’ve introduced to Ultimate from other sports tend to relish flow and have a disdain for stacking – perhaps the majority are Intuitive players.

hammer-layI recommend you check out the original article – Intuitive vs. Analytical Thinking in Ultimate [link], where Alex (an Analyst) talks more about the science behind the different personality types, and describes his frustrating attempts to learn how to cut effectively from an Intuitive player, plus the impact that conversation had on him as a player and a coach over the course of the following few years!

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University Taster Sessions Guide

This article is aimed at University clubs who want to recruit and develop players from a very large, very inexperienced group of freshers turning up to taster sessions at the start of the year. This is a guide for how the returning players can teach basic catching and throwing techniques, and how to behave in the games to ensure everyone has a good time and wants to return. When experienced players are able to teach basic techniques to incoming players, the speed at which freshers improve increases dramatically, and when experienced players know how to play in a fresher-friendly way during the first weeks of term, the retention of players skyrockets. The first step to getting this working within your club is to connect with the returning players before term starts, and make sure everyone is on the same page when it comes to interacting with the freshers.

Throwing around

When a fresher arrives at their first training or taster session, they should be welcomed by an experienced player, and invited to throw a Frisbee around for 15-20 minutes – in pairs or in as small a group as possible, with one experienced player per group. After a few throws, the experienced player should ask if the fresher would like some tips on their catching or throwing. It’s important to ask this question and get a ‘yes’ answer, as then the fresher has psychologically ‘bought in’ and will be eager to listen to what you have to say. Make sure the first thing you do is pay them a compliment.

When teaching catching technique, focus on just a few important points:

Move your feet to get your chest behind the disc
– Use both hands, clap catch in the centre of the disc with both hands hitting it at the same time
– Watch the disc into your hands

Throwing technique involves four sequential points:
1. Footwork – step out wide at 90 degrees, bend at the knees
2. Grip – fingers tight inside the rim for the backhand (index finger where it feels comfortable); power grip for the side-arm (index and middle finger together, not split)
3. Release (backhand) – rotate body, drop shoulder, coil wrist, release at or below knee height, with outside edge pointing slightly down
4. Spin – snap the wrist more

The order of these four points is critical. Don’t teach the fresher about grip until they have their footwork sorted, don’t teach them about the release until they have their grip sorted, and so on. Focus on one point at a time, give them a compliment every time you give them a tip, and try to relate the usefulness of the movements to the game. Remember at all times that you are setting an example with your own throwing and catching, and a lot of players learn by watching rather than listening, so be a model player with clap catches at your chest and wide, low pivots – “classic” technique.

Playing Ultimate

After these 15-20mins of throwing in small groups, it’s time to play. Remember that when a fresher comes to Ultimate practice for the first time, they don’t want to learn how to play great Ultimate; they just want to play. They certainly don’t want to be told to stand in a line and run in a particular direction for no apparent reason, so skip any drills and go straight into games.

Split the players into groups of 4-6 beginners with 2 experienced players, to play 4v4 / 5v5 games (not 6v6+). Whilst the pitches are being set up, the 2 experienced players per team should briefly explain the basic rules and have a chat for a few minutes to get to know their team. Make the pitches big enough for a good run around – 20 meters wide by 40 meters long with 3 meter deep end zones is reasonable. If the beginners can be split into groups with some pre-existing connections (friends, living in same accommodation, course mates etc.), this is even better and will really help retention.

There are 5 basic rules for the experienced players to explain in their teams:
1) You score 1pt by catching a pass in the opposing team’s end zone
2) You can’t run with the disc – it can only be advanced by throws
3) An incomplete pass (drop, throw away) or an interception (knock down or caught) is a turn over, and the other team get possession going in the other direction
4) It’s non-contact, so you can’t yank the disc out of someone’s hands and there’s no pushing before/during catches
5) It’s self-refereed, so call your own infractions and decide between players what happened and how the game should continue.

It can be good to talk more about Spirit of the Game / self-refereeing before the games start, and during the game make sure that everyone stops for any clear fouls & that the related rules are explained to the players, who should come to their own agreement about what happened. Freshers won’t often stop the game – you have that responsibility.

Below are some general points to remember when playing Ultimate with freshers so that they have fun, learn, and want to come back. When on offence:

– Let freshers pick up the disc if they want to. Progress to calling a couple of people at the start of the point who will pick up the disc and make sure you rotate through everyone.
Throw slow, flat, easy to catch passes, both for short and long throws, even if they are easier to intercept.
– Throw when the cutter wants it, even if you know it’ll be intercepted. In the worst case, the defender does a good thing, and your team mate feels you trust them.
– Let your team know you’re always there for the easy pass if they need it, but don’t demand the disc, don’t reprimand speculative shots, and try to always be a hittable option for the thrower.
– Don’t teach a formation (such as stack) unless the freshers ask about strategy – it’s too much information at this point. Better to work from principles around creating and using space. Under no circumstances stand over the disc waiting for everyone to ‘stack up’, or pick up the disc and demand ‘cuts’. The game might seem like chaos, but this doesn’t mean the freshers aren’t enjoying themselves more than they would if it were disciplined.
Put up long shots, especially if it’s getting crowded around the disc. This will encourage deep cuts and throws in future points, and will also give freshers the unique experience of chasing down a long throw… an experience which in itself can be enough to get a fresher hooked.
– Ensure everyone is getting disc time by being mindful of who you’re looking to pass to. Calling a ‘string’ play helps with this (player A looks to player B, who looks to player C, etc.).

Then when on defence:

– Don’t teach the stall count (or stall anybody) for the first week, it only adds pressure and complicates things. Forces should be loose.
– If marking another experienced player, let them get free when and where they want around the disc. After summer it’s tempting to play hard against your peers, but you must resist. If the experienced player you’re marking goes for the end zone though, go for an amazing interception.
– If marking a beginner, let them get free too, though mark them out when they start clogging space around the disc as it’ll encourage them to clear out. If the genders on the pitch aren’t balanced, it can be better for an experienced player to mark a female fresher instead of another experienced player.
No poaching. It’s not a challenge to get a poach D in a game with beginners – especially when you’re already out of position due to letting players get the disc as detailed above – and it’s not fun for anyone else.
– No point blocks or even stopping break throws – you want throws to either be completed or be intercepted by beginners. If an experienced player wants to break you, let them. If a beginner looks like they’re going to throw it into your force, get out of the way. Don’t let your team know you’re not pulling in the same direction as them on defence – make it look like you’re concentrating and playing hard – but be ineffective.
– Don’t teach strategy, such as forcing one way, unless the freshers ask, or if you’re nearing the end of the session and your team has a good understanding. Better to work from principles and simple instructions – man defence can simply be explained by saying, “if they throw the disc to your man, catch it before he does”.
– When marking confident or athletic beginners, raise the intensity to give them a proper challenge. Some freshers won’t come back if you intercept their throws or mark them out, while other freshers won’t come back unless they get a tough challenge and are shown what they can achieve, so play it by ear.

In general when playing a game:

– When two experienced players are involved in a foul and have a subsequent discussion, remember you are setting an example for all the other freshers, so explain your point of view honestly, clearly and respectfully, and settle the call in the ‘proper’ fashion – a joke between friends may be misunderstood by freshers.
– For violations such as travels, picks, and close in/out calls, and not quite being in the end zone for a score, only stop the game if it’s a fresher who notices the violation – even if it affects the play, it’s much better for the game to continue if the freshers don’t notice.

Finally, remember it is your responsibility as an experienced player to ensure everyone on the pitch is having a good time, and not just your team. You could be scoring every time and thus feel everything is going great, but think about your opposition, and adjust your tactics accordingly (having your weaker freshers pick up the disc, for example, or attempt an exciting deep throw against their best defender).

Exit / retention strategy

After the games it’s good to circle up and let the freshers know how your club works – for example, everyone is welcome to continue coming along even if they didn’t have a good practice that day, and that over the year they’ll all be taught everything they need to know to go from a noob to a good player. Mention beginner tournaments, fun tournaments, the BUCS league and Nationals, so you’ll retain the competitive freshers who will be trying to get onto your 1st / 2nd team from the start, as well as those who simply enjoy the game and will make your club socials great. It can be good to have a big game (like a showgame) after everyone finished, so let everyone know that some people are going straight to the pub (on campus near where you train, hopefully), and some are sticking around to play a quick game of 7 vs. 7 first, where freshers are welcome to join in.

This game should be on a full size pitch, with as close to a 4:3 gender split as possible, and everyone playing proper, hard Ultimate, hopefully showing what the freshers can aim for. Again, don’t call picks or travels, but do call and discuss fouls properly when they occur. After a couple of points invite freshers to get on the line and join in – there will always be a few that are keen. Make sure the experienced players try to persuade their team mates from the 5-aside games to get on the pitch, and to sub out for any freshers that show interest in playing. You may only get a handful of freshers joining in, but they will likely love the experience of being on a big pitch with so many experienced players, and they’ll appreciate greatly how they have been given the opportunity to play in a fairly high level game at their first session.

After the session, make sure as many freshers as possible come to the pub, and then talk to them! It’s very tempting to catch up with your team mates who you haven’t seen all summer, but there are better times for that, so be mindful of who you’re chatting with. Go out of your way and make it your responsibility to get every fresher talking, as it can easily make the difference between them never coming back, and them captaining the team in two years time. The confident and athletic freshers will want to hear about the GB Junior and GB U23 opportunities available to them if they stick with Ultimate – they want to be challenged and they want to know it’s possible for them to achieve greatness. There will also be freshers who want to take up a sport but hate the ethos of rugby and football so now is a great time for them to find out if the vibe of your club is something they can enjoy.

By applying the advice given here at your taster sessions, your freshers will hopefully enjoy their first experiences of Ultimate and become hooked in no time. By ensuring all experienced players learn these guidelines before the fresher intake each year, hopefully the recruitment and retention rates for your club will keep growing, and thus lead to huge performance gains.

– Felix Shardlow
Felix has been coaching the Sussex University Mohawks since 2003 & Brighton Panthers since 2011

The fallacy of “No Breaks”

We’re all familiar with the following situation; our team has turned over, the player we’re marking is walking to the disc, we’re putting a force on, and our sideline helpfully advises “No breaks!”


Photo by Graham Shellswell from The ShowGame

At this moment in time, not being broken is pretty much your only aim. If there was one thing you were planning on avoiding for the next few seconds, it’d be being broken by the thrower. You know this is not an easy task, but you’re going to try your hardest. You’re remembering the release points of your mark, you’re glancing over your shoulder to visualise the potential threats, and you have an extra pair of eyes on the sideline to help you. What do they say? No breaks. Guess you’re to blame if you get broken then – the instructions couldn’t be clearer.

Another situation we’re all familiar with – the opponents break the force, and the shout of “No breaks!” rings out again – usually in a more whiney tone. The force has already been broken – all the shouter is doing is releasing their frustration in a commonly acceptable way. You wouldn’t shout “Don’t get scored on!” before or after the opponents score, would you? Everybody knows what you were trying to do, and that you didn’t succeed in doing it – no need to state the obvious.

The real fallacy of ‘No Breaks’ isn’t in how obvious, unhelpful, or useless it is as a hindsight, but in the near-impossibility of the request. When two players of comparable ability face up against each other, the thrower will be able to break the force. We’ve all been part of drills since we were beginners where breaking the force is a given. The three-man break-force drill doesn’t pose any real challenge to the throwers – without any restrictions on time and space, breaking the force is easy, and stopping all break throws is incredibly difficult.


Photo by Simon Crisp
What a force can be expected to do though, is to stop throws to a particular space at a particular time. The force knows very little about which particular space and which particular time – their main indicators come from what they can see (the thrower – where they’re looking / pivoting), and what they can hear (sounds of players behind them / cutters calling for the disc).

The sideline have access to far more information. They can see space developing behind the force, and instruct the mark to move to prevent throws to this space. Conversely, they can also see where covered cuts or crowded areas are behind the force, and instruct the mark to force throws to go towards these areas. Sideline players can identify a free offence player cutting and provide very timely shouts to help the force prevent the ‘easy’ throws to them.


Photo by Christine Rushworth from The ShowGame

Most higher level teams have their own lexicon for communicating some of this information – ‘left hand / right hand‘, ‘around / inside’, ‘strike‘ and ‘spoil‘ / ‘no huck’ calls are quite common, and each are useful for encouraging the force to concentrate on taking out a particular throw at a particular time – infinitely more useful than a ‘no break’ shout. This allows the force to direct their efforts in the most effective way.

The sideline can also help the force by letting them know more general / less situation-specific information, so as what the thrower’s preferred throws are – if they’ve been using high releases to devastating effect, then communicating ‘high hands‘ can benefit the defence. If the thrower is going into the wind, then ‘low hands’ can force higher release points, therefore tougher upwind throws.

At the next opportunity when your team mate is stepping up to put a force on, trust that they know the basics of the task at hand, and communicate to them using the info they can’t see or hear for themselves. It’s time we heard the last of “No Breaks”.

Offences vs Defences: Training to counter your opponent effectively

Introduction:

In this article I will be seeing how a selection of common offences match up to a selection of common defences in Ultimate, and whether any conclusions can be drawn about the most effective offences / defences for teams to spend time learning in order to efficiently counter their opponents’. When planning what strategies your team should learn in any given season, it’s important to know what their strengths and weaknesses are, and how they are most likely to be countered effectively by your opponents.
The strategies listed are by no means exhaustive – every strategy has several different ways of being played, several tweaks or modifications, several patterns or plays which can be employed – none of which are touched on here, for the sake of simplicity. Environmental factors are not considered, “match-strategy” is not considered (e.g. come out more aggressive at the start of a match; change your defence regularly), skill-sets of teams or individual players are not considered, and different teams will have experienced different levels of success with the strategies listed – these estimates and statements are generalisations, made in order to achieve some kind of tangible comparison between the offensive/defensive strategies based on their merits and drawbacks.

I’m working with four offences and four defences:
Vertical / side / split stack offence: Players line up in the centre or at the side of the field, and make hard ‘cuts’ to the space available, before ‘clearing’ back into a stack. One player stays behind the disc as a dump/reset.
Horizontal stack: Players create a 3-4 formation (3 backfield, 4 downfield), with the downfield players either cutting towards or away from the disc.
Hexagon offence: Players form a hexagon made from equilateral triangles, often in a 2-3-2 formation, with movement creating space for passes in any direction. More info on Hex offence here.
Zone O: Varies from team to team, but usually 3 or 4 players in the backfield, who swing the disc from side to side, looking to pass downfield to ‘poppers’ attacking the space in front of the disc, and wings or deeps further downfield.

Strict person-D: Each defender marks an offensive player, staying very close to them for the duration of the offence. The side the defender tries to hold position on their mark is determined by the direction of the force put on the thrower.
“Help-defence”: A modification of person-D where the defenders are heads-up to switching marks and helping covering dangerous space when appropriate. More info on Help-defence here.
Flexagon: A hybrid defence, taking elements from person-D and Zone, to apply pressure to all players by using constant teamwork and communication. In theory a 2-3-2 setup, but actual positioning is entirely dependant upon where the offensive players are. More info on Flexagon D here.
Zone D: Defenders spread over the field to cover the space, usually overloading the area in front of the thrower to limit short downfield throwing options. There are many types of Zone D, this article does not distinguishing between them (for simplicity).

defence
* a note about strict person-D: although much pressure can be applied by playing this defence with smart local positioning and trained athletic moves, I see the strategy as limited due to (a) the absence of teamwork between downfield defenders, and (b) the over-reliance upon matching or surpassing your opponents athletically.

offence

Calibration:

The table below compares each offence against each defence. The numbers are scoring likelihood / defence likelihood estimates, assuming two high-to-elite level teams are competing with well-practiced offences vs well-practiced defences. For example, assume the (very common) combination of Vertical stack vs strict person-D would see the offence scoring without turning over 85% of the time – use this as calibration for the other numbers, whether or not you agree with the figure! This is roughly the same for Horizontal stack vs person-D, and for Zone O vs Zone D – these combinations are generally considered comparable with each other in terms of effectiveness, as they are the most commonly played.
“Help-defence” is more variable than the others, as it depends a lot on how well it is played by the defence, and how well the offence adapts – so I’ve given the numbers a range.
Hexagon and Flexagon are quite new strategies, so the estimates are more likely to be inaccurate, however they are taken from 2-3 years of regularly teaching and playing the strategies – including with the GB U23 Mixed 2015 team.
All the numbers are rough estimates of likelihood, and the relative effectiveness of each strategy will certainly vary from team to team, and depending on how each is played!

o-d-matrix

From an offence point of view:

vs Strict person-D, it’s best to get defenders clumping together (covering the least / most useless space), so a vertical or side stack is ideal, and horizontal creates a large deep space. Hex spreads the defenders out, meaning the D actually becomes more efficient.
vs “Help-defence”, defenders who are clumping together will be able to poach/switch to help each other, so vertical stack becomes less effective. Horizontal spreads the defenders well, making it hard for them to help each other effectively – especially when it comes to covering the immediate deep threat. Hex spreads the defenders further and punishes poaching more efficiently, but doesn’t offer the immediate deep threat of Horizontal.
vs Flexagon, vertical stack is negated, and Zone O doesn’t function well due to the tight marking against static players. Any set cutting patterns of plays are unlikely to work, so Horizontal stack and Hexagon must improvise in order to function. Improvisation is easiest done when the number of available options is maximised, so Hex is the ideal setup.
vs Zone D, stack offences are negated. Zone O and Hex have both been shown to be effective at breaking down area-based (zonal) defences, so should be played to counter Zone D.

From a defence point of view:

vs Vertical / Side / Split stack offences, the offensive players are clumping, so strict person-D plays to their strength (clumping your defenders together and leaving large open spaces), whilst Zone or Flex will force them to transition into another offence. Help-defence punishes the clumping, which encourages the offence to improvise, and can generate turnovers when played well.
vs Horizontal stack, the offence is more spread, so help-defence is harder to implement. Strict person-D is moderately effective as usual (depending on your athleticism vs theirs), but Zone D or Flexagon will force the offence out of any pattern- or play-based movement.
vs Hexagon, simple person-D can cause issues, specifically if you are more athletic than your opponents. Help-defence is easier punished by Hex than other offences, but can force the offence to use all their options. Traditional zones don’t change the formation of the Hex, but can force a different play-style which the offence may not be used to. Flexagon applies pressure to the highest number of options, forcing the offence to improvise – meaning any set patterns or plays become unreliable, and players must identify space for cuts and passes as and when they appear.
vs Zone-O, the offensive players are looking for space to occupy, so person-D will force a transition. Zone D conserves the energy of most defenders, however Zone O will be well-practiced against Zone D. Flexagon is more person-focussed, which forces Zone O either to transition or to improvise – to play at a different pace/tempo than they are used to in Zone O.

Summary:

From an offence point of view: The most common defence is strict person-D, and the most common offence – vertical stack – does well to exploit strict person-D’s weaknesses. If the defence start switching and poaching (“Help-defence”), then the offence must start to improvise, and would ideally be able to counter with a practiced Horizontal stack or Hexagon offence. If facing Flexagon, offensive improvisation from a Horizontal / Hex / Zone O setup is necessary. If the defence play Zone, then the offence must respond with a practiced Zone O or Hexagon offence.
From a defence point of view: The most common offence is vertical stack, which plays to the weaknesses of strict person-D. Playing Flexagon or a Zone D will force the offence to transition – and you will see if they have a practiced alternative. Zone O can be countered effectively with person-D or Flexagon, which forces the offence to either completely improvise, or to play Horizontal stack or Hexagon offence. Flexagon still functions well against these offences, as does person-D – providing there is no athletic disadvantage.

Conclusion:

From an offence point of view: Time spent perfecting a vertical stack offence can be made to be ineffective if a defence plays anything other than strict person-D. Training an offence which works against Zone (i.e. Zone O or Hexagon offence) is essential. If your opponents have good “Help-defence” or Flexagon D, then you must either be able to improvise, or transition to Horizontal / Hexagon in order to keep your scoring percentages up. Horizontal must transition when facing Zone, but Hexagon can be played effectively against any defence you face – even though it may not necessarily be the most effective against any defence individually. Your team can function against any defence if they know both Horizontal (with improvisation) and Zone O, or if they simply know Hexagon offence. To be the most effective, a team should also learn an offence which punishes strict person-D more efficiently – vertical- or side-stack.
From a defence point of view: Strict person defence is simple to learn and functions against any offence, but its success is determined by the athletic edge you have over the opponent, and limited by the lack of teamwork involved. If you have an athletic edge over almost every opponent then strict person-D can get enough turns to win games, but only until you reach an athletically superior team playing a well-practiced offence, or until your own offence is countered. Learning a more challenging defence, particularly one which counters the most common offence – vertical stack – is essential, unless you are fully relying on your athleticism or your offence.
“Help-defence” is hard to learn and implement due to its lack of structure and principles, and it is most useful against vertical stack – less so against Horizontal or Hex. Zone D completely counters vertical and other stack offences, however most teams have a well practiced Zone O which will counter it well. Although Flexagon is also hard to learn, it is flexible enough to be played effectively against any offence you face, countering the most common vertical stack and Zone offences effectively.

More info on Hex offence here.
More info on Help-defence here.
More info on Flexagon D here.
Video of Flexagon D in action.