
Originally Posted by
Shurrikhan
It is unless you Holy Shelltron, Bloodwhetting, and Heart of Corundum would have mitigated ("nullified") and healed more than 25% of your HP over their durations.
Mitigation amounts to your aforementioned "nullification". If it "nullified" nothing, it'd have done nothing. 25% mitigation that spans 12k would-be damage will "nullify" 3k damage. That is its value.
That value is not changed by when it or at what pace it did that mitigation because the only pertinent part of that, the fading percentile mitigation as you drop from the first to latter 4 seconds of their duration, is already accounted for in the damage nullified. It is not changed by having died early, because that would likewise have changed the total damage nullified. A mitigation tool's value is, simply and wholly, what is has nullified.
We could add effective healing atop that, which would then have its mirrored factor in being wasted by overhealing -- or what would have, a tick later, have been overhealing -- but such would again be accounted for right there in that metric. That it is a HoT or single heal would have no bearing on its total effective healing.
A shield that crumbles to dust after nullifying 3k damage does exactly the same amount of mitigation as an 8-second duration effect that ends up nullifying 3k damage. TBN gets outscaled only under extreme values of damage taken over 8 seconds. And for all short of that, TBN outperforms its competitors.
Let's say you're a tank with 12k HP. A TBN is therefore 3k. Subtract the healing the competitors could do from that value and you have 8 seconds then to make up the difference.
If you can make up the difference in under 8 seconds, the competitor comes out ahead; if it can't, TBN comes out ahead. And there are plenty of situations where you cannot make up that difference, and TBN will therefore come out ahead.
There is, again, no inherent further weakness to front-loaded mitigation; it's simply a matter of which nullifies ("mitigates", in normal people talk) and resets ("heals") more damage.