Baffling behavior

[Skivvy]

But in general the must keep all hp bars at 90% full at all times healers are actually kinda bad healers.

Just wanted to add, keeping HP at 90% all the time is a bit excessive for most content. With how scripted fights are, it's easy to learn which moves are tankbusters/aoes, what move is next, etc, and healers can adjust their DPS/healing accordingly. Obviously there are exceptions where you may want or need to babysit HP more, but generally we have a lot more wiggle room to play with.