I don't understand why people are attacking this comment, in FFXI stunning was a staple strat to some fight especially on mobs that had a set time before releasing an ability to the party.
Also I'm not sure if others have brought this up but perhaps we have forgotten about the ability to attack body parts to weaken the enemy, it's possible there may be abilities that a class can use to weaken the mob but there hasn't been enough time to test it yet. While sure people will most likely go with the path of least resistance doesn't mean it's the only option or that the mob is to overpowering. It's all trial and error if anything, for people that don't mind taking the risk make sure you have abilities that target monster body parts active and just spam them to see if it has any effect in weakening the boss.