I looked back at the text of the post and it says "any helpful spell" which includes buffs... That'd be so aggravating to trigger it's ICD every time you rebuff someone.
If they limited it to proc off of certain spells or CDs (like Pain Suppression or Guardian Spirit) that you'd use only in high damage situations, then maybe they could avoid that problem? The only issue I'd see with that is that Priest healing is highly situational and customizable... One priests' strat for a fight may be totally insane to another, but they can both manage to do their job. =\