Atonement is a passive effect that is triggered by the game mechanics. Not quite a Programmed Random OCcurrance, but it is "a chance to heal" the right person. And let's be real here, Holy Fire does this already, but each tick is less than a 0 mastery Shaman's Healing Rain. It doesn't count as an AoE splash, it's just residual. Penance, you're giving up... your strongest single target heal for a mini cleave that may or may not spread (you can't force it to cast on three separate people), and each tick heals less than Grace.
Sure, I can see it potentially pretending to be useful on fights with damage buffs (Zon'ozz, Staghelm, Halfus), but a cleave won't do as much as a Prayer ever could in a PvE situation (And a Penance on a person hit harder not only triages them back up, but makes the Prayer actually do more as well).

MMO-Champion
