Originally Posted by
Kelesti
You stuck in 3.0 or still only doing 10 mans? In 25's, they can't keep up with tank damage the way a Holy Paladin can. They can't raid heal like a Druid can.
But they can flow between the two quite seamlessly, their role being to "assist where necessary" and shift accordingly. A Discipline Priest assisting the raid while focussing a tank not only recovers from "Impending Tank Death" for those bursts that have your Paladin falling behind, but also keeping the raid members alive long enough to get topped off from someone else (be it druid, shaman, priest, or splash damage from a trigger happy Paladin, nobody cares).
There's a reason every serious guild brings a Disc Priest to hard mode 25 progression. But they're far from tossing your Holy Paladins (which they're still bringing, by the way) to the unemployment job, because they just can't keep up with the single target damage when Penance is on cooldown.