Based on the number of one-shot mechanics in the later CEs, I get the impression SE has decided they just can't challenge healers in terms of healing output, so the best way to do it is on Raise throughput instead. Either that or they intend it to be "go farm those potions that give you more defense before doing stuff" because those things are incredibly strong in that they let someone learning a new CE actually stay alive long enough to learn it instead of being instakilled by everything.

It works fine if people already know what they're doing, but get a group for something like the Behemoth CE while half the instance is in Castrum, and you'll get a bunch of newbies to the CE who don't know how it works. That means it'll be over in about 30 seconds when every single person dies to one mechanic they haven't seen before.