I've said previously, I'll say it again, adjusting tanks kits (and I stress adjusting) is only part of the answer and alone simply treats a symptom of the problem rather than addressing the problem itself. If nothing does enough damage to threaten us then what need is there for tanks? Much less healers. Therefore while reining in the most egregious tank skills is something that should happen, it should be in conjunction with a general rebalance of incoming damage throughout the game. I did Copperbell Mines just now and a telegraphed AOE on second boss did more damage than first boss' tank buster, my pocket tank who previously defended this tank buster when I mentioned it to them previously suddenly saw my point, it did 95 damage to them with no mits that I saw, that is to say "it did nothing, if not for the flashy effect it wouldn't have been noticed at all". Sure, this is baby's third dungeon and baby sprout is learning, so why are they being taught that what tank mechanics exist are completely ignorable?

While I might not advocate for the first tankbuster you see being multiple times the tank's HP and insta-killing an unsuspecting player (though I DO advocate that past level 50, your basic tutorial is OVER at that point, time to start improving your play), it should be enough that both tank and healer are forced to pay attention and learn that tank busters are actually a threat.