As a PLD main, I only have one concern with this and that is the cast time/animation lock for it. If I'm in a fight where I only need to OT, it'd be somewhat alright provided I didn't have to worry about the MT dying when both healers go down. If I am stuck on that good awful long cast and the MT dies, then that's no good either since if I don't stop the cast and pick up the boss then the group wipes anyway. Besides, SMN can also do am insta-cast raise, so you do get 3 in combat raises when you have a SMN in your group (something I've had to do on more than one occasion, actually). But once again, useful only in very select circumstances.