Nonetheless, I'm trying as best I can not to let my personal dislike for the Dampening debuff cloud my judgement. So, with that effort to be objective in mind, why shouldn't Dampening start at 5 minutes, rather than 10 minutes where it is now?
1. Regularity of appearance
The vast majority of arena matches, particularly in 2v2 where Dampening is arguably the most needed, last less than ten minutes. Therefore, it's currently relatively unusual to even run into this debuff. Certainly, it's not the case that it never happens, particularly when you have healer-DPS versus healer-DPS at a reasonable rating. Back in October, Community Representative Lore talked about how Dampening wouldn't favor double DPS comps as, at 10 minutes, matches would "rarely if ever" last long enough for the debuff to kick in. While it's still less likely to appear in double DPS matches, moving it to 5 minutes will make it a far more regular occurrence.
2. It's supposed to be a match ender
Dampening was introduced to replace The Crowd Chose You, a buff which used the carrot approach instead of Dampening's stick, by assessing health levels through a match and awarding the team who maintained the highest health a buff that allowed them to one-shot their opponents. As flawed as this system was, it's its premise that we're interested in, and that was to prevent draws and turtling from players to prolong matches they'd lost, or couldn't win, and have them result in ties. This was favorable, as ties usually result in a lower rating loss than straight losses.
Dampening, while different in many ways, is intended to have the same effect. And at 10 minutes, it does. While it isn't always that effective (and we'll get to that), it does at least make it harder and harder to heal. It takes a match that's running longer than the average, and makes it harder and harder to extend it any further. At 5 minutes, it's taking a match that's run a perfectly normal length, not longer than the average at all, and attempting to bring it to an early close. That's not what The Crowd Chose You was intended for, and nor is it what Dampening was initially trying to do. There's already a timer on matches, although depending on rating it's very rare to reach it. We don't need Dampening at 5 minutes.
3. It favors certain classes and comps over others
While Dampening affects all healers' healing and absorbs fairly equally, one thing is doesn't affect is percentage based incoming damage mitigations. Some healers have more of those than others. And of course, the strongest healers of the moment will do the best out of Dampening. It will make the balance differences more stark. It seems like Druids are particularly strong under its effect, although as I don't play a resto druid myself I couldn't comment on why.
But apart from the healing side of it, healer DPS is an issue. When your primary function is being taken away, you fall back on your secondary ones, and for several healers dealing reasonable DPS is that function. Some healers deal a lot more DPS than others, and those healers will do better in Dampening, not as healers but as DPS. For example, Boetar of Bleached Bones, playing a resto druid at BlizzCon made brave switches from healing to DPS when Dampening kicked in, and won games. Resto shaman, for example, have famously terrible DPS.
What's more, we touched upon this issue earlier, but with Dampening at 5 minutes rather than 10, it's far more viable and likely for teams to turtle until 5 minutes, then start to attack. Sure, the debuff builds up slowly, but nonetheless, it's something to consider. The devs even had it on their radar with the original implementation. In larger comps than 2v2, it is also a possibility that this will favor rush comps over drains, and that's a consideration. I definitely don't think this is a major design issue, though.
4. If it ain't broke, don't fix it
This is one of the biggest arguments for me. There is nothing wrong with Dampening at 10 minutes. There have been barely any requests for it to be moved to 5 minutes, and that's simply because it doesn't need to be. Dampening at 10 minutes, much as I personally dislike the debuff itself, does its job and brings matches to a close. I do think there are several better ways this could be accomplished, but for now those are neither here nor there.
Sure, people might enjoy the move, some DPS certainly will, but as a main healer myself, I won't. I would know that I only have five minutes of a match at my maximum effectiveness, regardless of how well I play. I have less than the average time of my matches to do my job at my best, before something I have no control over removes that, slowly. But more importantly, there's just no need for it to happen. It was nice at BlizzCon, because, for an audience and for a time-restricted tournament, the faster the better. While the same may apply in some cases on live servers, things moving a bit more slowly is no bad thing.
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