I've used it on my healer a few times. I've had random mobs blind / fear me, and someone in my group would have died without me being able to break out of it. I also survived a dungeon wipe where our group had to run to the zone-line once. I got CC'd and would have died without it. I don't think it's ever actually truly bad for any class.
Don't quote me on this because I could be wrong, but I believe I heard Kriddle say on one of his streams that the Traits may be updated before EA. I would be surprised if they leave this one in it's current state just because it seems to be a little too good compared to a lot of the alternatives.