I have been wondering this as well, I would assume if you had one tank to control the agro and keep mobs at range, the priests could dot the crap out of the mob and mindsear the mobs individually.

In my mind it works well, especially the physchic scream and fade as a threat detterent.
Plus the healing and mana regen from vamp touch/embrace...


Hmmm, you might be on to something, yet I can't see any footage of anyone making it work...