I'll say this:

You putting less strain on the healer by not eating aoes goes a LONG way than a dps not hitting positionals on trash.

A NIN need to refresh Huton? He'll just have to do it with Armor Crush without doing it on the side. A DRG needs to refresh Blood of the Dragon while Wheeling Thrust is up? He'd better hit the attack from the rear while running out the aoe zone.

That tank that eats all aoes to save the dps' positionals? Good luck not getting complaints from the healer. Heck, even the dps will ask you why you're eating the aoes.