As a matter of opinion, I've found Disc to be better at just about everything besides Raid Healing. Holy has the uncanny ability to spread their healing out with a lot of set-and-forget abilities and some pretty awesome smart-heals. But that's about the extent of it.
Discipline allows for far more powerful healing. It also allows for smite-healing which is absolutely awesome for easier pulls. It's going to depend on your situation, on a pull-by-pull basis, but if you're going with a good yet under geared group, Disc will outperform Holy by a solid margin. Don't be afraid to use Pain suppression, and basically use the rest of your cooldowns as they pop up, and you'll be fine.
Penance to get Grace3 up, make sure you grab Inspiration.
Greater Heal for Train of Thought.
Heal for Strength of Soul.
PW:S for Rapture and Renewed Hope. Only PW:S if you know it'll break.
Never Renew. Never Flash Heal.
Those are the rules I played by. Now, unfortunately I have to be Holy for Raid heals and it's a lot of fun, but when a Main healer goes down my HPS go from 15k to like 7k, it's rough, and honestly Holy Priest just stinks compared to Disc or Holy Pallies for Main Heals.
Regardless, though, you're going to be drinking A LOT. So stock up on water, make friends with Mages, and keep both on your hotbar. Drinking as soon as it allows will save the group a lot of time.
Edited, May 23rd 2011 12:39am by tzsjynx
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