So as some of you may be aware, I am part of a dedicated AD PvP guild who currently homes on Vivec, PC NA. We specialize in the 12-24 player combat style and have been active for several years now. I say "specialize" because that is, in fact, the most successful way to approach your build when you are running in a group of that size. Without going too far into raid composition, I can at least say that we have specialized healers, damage dealers, and various support builds. One of those support builds, for now, is responsible for "spamming" rapids. In truth it's a fair bit more complicated than that, but that is the public perception and the topic I'd like to address. Specifically, I'd like to go over the pressures that have led us to incorporate this kind of build, the difference in success rates at objectives after incorporating these builds, and the likely effects of taking away such builds in the near future.
First, though, I'd like to mention that the title is slightly misleading. While I do primarily run in a 12-24 player group, I also sometimes do smallscale or even solo play, and I have a lot of experience in no-CP battlegrounds. I may have a bias, but I've played a great variety of PvP styles to a considerable extent over the years, and offer the following credentials to demonstrate that I am not only thinking in terms of large group play during this analysis.

So to begin, let us examine what pressures exist which leads organized groups to run whatever is their preferred number of "stam support" builds. Primarily, this has to deal with the absolute ubiquity and overperformance of snare and root effects. The effects that snare include :
Templar
Puncturing Strikes (stam and magicka), Sun Fire, Sacred Ground Passive
Dragonknight
Warmth Passive (stam and magicka), Ash Cloud
Nightblade
Teleport Strike, Consuming Darkness, Aspect of Terror
Warden
Sleet Storm, Impaling Shards
Two-Handed
Stampede (morph exclusive)
One-Handed and Shield
Low Slash
Dual Wield
Rending Slashes (morph exclusive), Hidden Blade
Bow
Arrow Spray
Destruction Staff
Wall of Elements (ice staff exclusive)
Fighters Guild
Sliver Bolts
Mages Guild
Ice Comet (morph exclusive)
Undaunted
Trapping Webs
Psijic Order
Time Stop
Alliance War Support
Revealing Flare (stealth contingent)
Alliance War Assault
Caltrops
The effects that immobilize include :
Dragonknight
Dragonknight Standard (synergy required), Dark Talons
Sorcerer
Encase, Daedric Mines
Nightblade
Crippling Grasp (morph exclusive)
Warden
Gripping Shards (morph exclusive), Frozen Gate
Bow
Bombard (morph exclusive)
Destruction Staff
Elemental Rage (morph exclusive, ice staff exclusive), Wall of Elements (ice staff exclusive, status condition contingent), Destructive Touch (ice staff exclusive)
Fighters Guild
Trap Beast
Now in smallscale-V-smallscale, battlegrounds, and duels, the single-target snares really start to shine, but for large group play the snares that perform the best are the ones which affect a large AoE, and most especially the ground-based effects which can persist at critical location like breaches, keep flags, and any choke points. These are available to both magicka and stamina users of all types in forms like Caltrops and Time Stop, so regardless of class you always have quality AoE ground-based snares at your disposal, and many of the other AoE snares are still extremely strong and fill other niche roles, such as casting Arrow Spray while in a more mobile fight.
So that covers snare availability, but what of their overperformance? Well, all of these movement impairing effects snare for 30% at least and 70% at worst. That is to say, they automatically counter the Major Expedition buff (the strongest movement buff in the game) at the very least, and in a large area of effect to boot, with extraordinarily few ways to prevent the snare from happening.
Before jumping into counters, let's see how easy it is to get Major Expedition. To wit, we have the following :
Dragonknight
Fiery Grip (requires target and self-displacement)
Nightblade
Double Take (morph exclusive), Path of Darkness (only while in in are of effect), Cripple (requires target)
Sorcerer
Boundless Storm (morph exclusive)
Bow
Hasty Retreat (requires roll dodge)
Dual Wield
Quick Cloak (morph exclusive)
Vampire
Elusive Mist (morph exclusive)
Alliance War Assault
Rapid Maneuver
Only two of these sources (Path of Darkness and Rapid Maneuver) offer an AoE solution, and Path of Darkness is notably useless (requiring you to be in a specific area) and Rapid Maneuver drops off as soon as you buff (with some exceptions), heal an ally, or cast a damaging ability.
Now let's look into counters. The following apply an immunity to snares :
Dragonknight
Reflective Plate (morph exclusive)
Two-Handed
Berserker Rage (morph exclusive, requires target), Forward Momentum (morph exclusive)
Medium Armor
Shuffle (morph exclusive, requires 5+ Medium Armor worn)
Alliance War Assault
Retreating Maneuver (morph exclusive)
Of these, only Retreating Maneuver provides an AoE option, and it falls off like its parent skill as soon as you buff, heal an ally, or cast a damaging ability.
As you can see, we have an incredible availability of snares in the game, with several powerful AoE options available to all builds, but very few sources of Major Expedition (which is not even guaranteed to fully counter the snare) and far,
far fewer sources of snare/immobilize immunity, of which we only have a single AoE option. If we consider normal movement speed to be the expectation and imbalance one way or the other for in-combat movement speed to be indicative of overperformance, then snares are overperforming by far, by a few dozen percentage points on average.
So knowing that snares are ubiquitous and overperforming, what are organized groups looking to keep up normal movement speed to do? The solution comes through specialization. We all have the option of changing up our builds to fit one of these remarkably limited self-affecting snare removals, which overwhelmingly favors stamina users, but this limits build diversity and is not an ideal solution any more than being responsible for your own heals is a good solution in a raid setting (it's not). If, however, you have a stam support character or two (or however many), then you can have them "spam rapids", which is to say Retreating Maneuver, the ONLY AoE snare immunity in the game, and in so doing you can keep your group from getting completely bogged down by snares. By continuously reapplying the immunity, you can minimize the effect of the buff dropping off every time you deal damage or heal, which for damage and heal build turns out to be close to 100% of what they do. Generally, then, you are only affected by those dreaded ground-based AoE snares for a fraction of the time you're in them, instead of 100%.
This does, of course, mean that with Rapids spam we might be slipping into an overal overperformance on the side of movement speed, since it also applies Major Expedition, but that depends on how often the buff is dropping off of you while you're in the snare, which
should be quite regularly. We should also, at this point, consider whether or not base speed truly is the appropriate standard for movement speed in combat. Should movement speed buffs be more like Major Brutality (completely ubiquitous, readily available, and standard expectation), more like Major Berserk (rare as an unclenched ass when getting destro bombed), or somewhere in between? I don't have a strong opinion on this and leave it as a point of discussion.
At any rate, it seems to me that, at the very least, being able to move at base speed, instead of moving with a snare, is the desired expected behavior, albeit one which requires exceptional forethought, build planning, and execution to maintain. And why should we be looking for normal movement speed when pulling off group maneuvers? Because the results speak for themselves!
As a veteran PvPer, I've seen a lot of metas come and go. This rapid spam meta is a fairly recent development, but the performance increase is exceptional. When moving over breaches, for example, we have a much better chance of successfully crossing than if we are permasnared with all the AoE ground-targeted slows. This is especially true at present, after the (frankly disastrous) changes to catapult siege, where you can now layer five or six overlapping high-damage circles courtesy of your favorite point-and-click heroes. That is overall a discussion for another time, but at the very least anyone familiar with normal keep defense and attack procedure should understand how critical it is to get over those breach choke points before the meatbag ticks eat you alive. There is already a significant difference in success just between snared and not-snared breach engagements, so it should not be surprising that Retreating Maneuvers, with its additional Major Expedition buff, is such an important skill.
Without these effects, many important, normative Cyrodiil behaviors like taking keeps become incredibly difficult and favor defenders even more than usual. Crossing the breach is one example, but other ones like pushing in to take/move across a flag, go up the stairs of a keep to clear oils, and other such projects are accomplished much more reliably without a snare on you. Otherwise you'll get bogged down in AoE, siege, and be much more easily outmaneuvered by the defending group(s), who do not have to worry about snares as much since they're first to put them out, and can simply wait for their opponents to push into a fight on their terms. They already own the keep, after all, so all things being equal they don't need to push out into the enemy-controlled courtyard in order to continue to own it.
As a corollary to this, these sort of dynamics invariably lead to keep turtling. Keep turtling would not necessarily be bad, but it has this nasty habit of eventually attracting more and more people to the fight, something that, if we are to face facts, the servers simply cannot properly handle at the moment. And we
should consider the facts on the ground when considering game design, not some distant theoretical future where all the lag problems are fixed, because that is the reality
right now and it negatively affects gameplay in the present, in a very real way. If the lag is someday fixed then great, we can revisit everything under the sun, but let's not hamper ourselves today for the promises of tomorrow.
Now, I'd like to bring up a point that no doubt many will not actually read far enough into the post to see, but which bears mentioning anyway because they're going to smugly mention it in the comments. Snares can be purged. It's true! Both the Alliance War Support skill Purge and the Templar Purify synergy from Cleansing Ritual will remove snares active on you. We even have a term for the people "spamming" purge : magicka support. Unfortunately, magicka support does not fit the needs for snare removal and immunity. In fact, magicka support roles
predate stam support by a significant margin, yet we still found need to create the stam support role.
There are two reason for their ineffectiveness : the Purge skill only removes two negative effects at a time, and as already described there are an enormous number of AoE ground-targeted snares. To the first point, in large group PvP you generally will have half a dozen negative effects on you at a time even WITH purge support. It's just the nature of the game. Just as there is an ubiquity of snares, so too is there an ubiquity of a dozen other negative effects, all of which are vying for those two slots that Purge can remove per use. To the latter point, AoE ground-targeted snares can reapply immediately after being purged. We don't at present have a snare immunity timer as we do with stuns and immobilizes.
Thus, it is ONLY Retreating Maneuvers that provides anything close to a counter for the overwhelming and overperforming snares, and even then it has to be spammed by dedicated builds to be noticeably effective. If you take away that ability then you are severely hampering the capacity of organized groups to have fair fights with each other. Keep battles will be even more extended than they already tend to be, leading to even more accidental giant zergs that the servers can't handle.
And who is actually helped by the proposed changes? Not small-scale players, who mathematically will never stand a chance against an organized raid. Certainly not ungrouped pugs, who will continue to die to the snare->siege combo they always get stuck on. And definitely not large organized raid groups, who are now getting their primary counter to such tactics taken away (unless they're defending the keep, of course). So is it.... nobody?? Well, no. It turns out that these changes mostly help large
disorganized raid groups, who already have a really great thing going for them just by running a larger number of players than any respectable guild would be caught with. It's not bad to have a numbers advantage, of course, but it is my opinion that a good game has a high enough skill cap, and mechanics that support high-tier play, such that good players can reliably defeat bad players even if they're a little outnumbered. I'd never advocate for a 2v60 situatio to work out, of course, but something like 40v60 or even 30v60 should not be impossible. Half is a good cuttoff point.
When you have such strong snares in your game, however, which lets the outnumbering faction manuever to zerg you all at once/siege you to space hell much more easily, and when you don't have adequate counters for the variety of snares you've implemented, then you're objectively decreasing the skill cap. It's literally a whole area of gameplay that you just have to live with, instead of plan around and counter. It would be like the whole Major/Minor Buff/Debuff system, except where you only implement the Debuffs and everyone is on fire and our cats are screaming.
So please, I implore you, do not implement this Retreating Maneuver change until
after you have done a complete rework of snares and movement. I do not want to suffer through months of slowhell for the other half of the problem to be addressed, which seems to be what was implied in
these notes on the most recent Class Rep Meeting. It's no good to roll out changes like this in pieces when you know that the overall situation in game is going to get worse as a result before it gets better with the rest of the overhaul. If there are devs who need help seeing what large-scale Cyrodiil battles are like, so that they can better understand this style of play and verify what I've said, then I'm absolutely positive that there are tons of guilds who would be willing to offer up a spot in group, for education purposes.
Then again, maybe I'm just underestimating the comedic potential of the Retreating Maneuver change. Taking less damage from behind could result in an Ass-First Blast Burst meta, where everything is the same except where all waddling towards each other buttwise and snared to hell so that we take 15% less damage when the enemy AoE goes off. Imagine the ratings spike.