Why? It's not like they are that good. I don't feel like nerfing my healing, gimping the raid, to heal someone for 50% of their maximum health, because they were too stupid and pulled threat, didn't use a defensive, or stood in poop. Powers of the Void isn't that good either. Why would I want to risk killing myself to save someone else's ass on a periodic basis? Clarity of Will is the only useful talent there imo.