Relief is on the way

[Concillian]

I haven't done any dedicated testing, but it certainly seems to me that melee mitigation and avoidance on the majority of Outland mobs has gone up a fair bit.

It has, some. Talents to help with it too.

My theory is that Blizzard was trying to get raiding people to spec into those talents by making boss AoEs HURT. It didn't work (rightfully so, since the talents weren't really powerful enough to justify it), so they're falling back to a different strategy.