Will depend almost entirely on the fight, ofc, but I'd wager it's ~50% of the 30% on average. It's usually in the downtime that we see that overheal (over-absorb?)...which is pretty obvious... but with them trying to "reduce 1-tank-ability" we may see more of that in this tier. Sure, we can cast it on the other tank, but unless we taunt-swap for V stacking, it'll be a pretty gimp shield.
I know that the HOLY version gets instant-on, but not sure/no clarifcation on if that applies to Prot/Ret as well. I'd be willing to bet no.
Even if we do get it though, as you and I have said, that gain will not offset the loss at all. It's really only a minor boost to taunt swap fights where you go from periods of low-V to high-V requently. On static fights, we have like one refresh for large gains (and then many small, stable/static refreshes).
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Right, but thats what I was referring to with "The ONLY change would be the first application after a V increase (and it'd have to be a BIG increase), where we get the new SS value ~3sec earlier. Over the course of a fight, this may happen 1-3 times, so you're looking at ~10 seconds of change." Specifically thinking of HC DA and HC LS here, as soon as I see V creep up to 150-200k I refresh it. The shield takes ~3 sec to update the actual absorb, but after that, it's cruise control.
So, even granting 3 of those "situations" (which doesn't exist on HC DA, but using HC LS as a format here between transistions to give extra credence to this point), you only get ~ 10 seconds of "benefit" from this change.
And that's only IF prot even GETS the Holy version of "instant-on".