I want to discuss some of the stuff I've learned, and perhaps educate some people out there who haven't deeply delved into this stuff. Perhaps it will inspire other Priests to go discipline or players to make a Priest alt. I would encourage this, because one of the issues with this spec is that it's very difficult to know if a player/character is doing their best unless you have more discs around to compare notes. Even then, disc is an unknown.
Discipline is one of those strange situations where player talent determines the outcome of so many situations. Because there is no "lolchainheal" or keeping hots on everyone there is planning that's needed. Some players plan badly, or panic badly, and disc will fail for those players.
Approaching disc from a "green bar goes up" perspective will get you into trouble. The only situations where that mindset won't repeatedly wipe you is when you and your group are overgeared. Hell, even in purples you will wipe on regulars with that sloppy mindset.
Druid healers may have an easier time with the discipline mindset. Druids (should) understand rolling hots, and that skill does apply to "rolling shields". I haven't done druid healing, so I'm not certain of this.
An understanding of preparing/timing overheals is also a skill that's somewhat portable to disc.
If you haven't played a druid, or if you have and don't have rolling hots down; if you haven't the intuition for timed overheals; or if you're coming from any non-healer background .. then there is truly nothing you can bring along with you that will help in the least. You're in a new frontier.
So what things would you need to learn to do discipline raiding?
They say that there are two kinds of discipline priests. A main tank healer and a raid healer. They are wrong.
Discipline is only tempting as a tank healer. There are lots of shiny-shiny abilities which are rather meaningless. In every situation I've been in, it's always more effective to have a "spot healer" role, switching between damage-prevention and "green bars go up" panic-healing to save lives. This obviously applies to 25s, where several different kind of healer are often available. But in my experience this also applies to 10s. I've had situations where raid success rested on the way I've healed. Tank-centric was an "oh so close" nice try, but a freer mindset that allowed more raid damage reduction was a baffling difference. This has also been true for me with two or three healers in a 10.
So let's think about the mechanics just a touch. I hate number crunching and it shows, but we can stop and ponder a little without going mad from the theorycrafting. There are two kinds of spell a Discipline priest has. One absorbs damage and the other heals.
Focusing mostly on the main tank means that healing will be leaned upon. Damage absorption happens once every 15 seconds from the debuff from a shield, and other damage absorption effects will proc from talents.
Un-focusing off of the main tank means that you will lean on instant-cast spells. Shields -- the bulk of your effort -- will be able to absorb at least some, and usually most, of their overall potential. This means that much more damage prevention can be achieved through raid shielding than by tank healing.
So on the tank we'd have shield and Penance for sure, and Flash Heal and/or Greater Heal (which is a separate argument), and sometimes Prayer of Mending (which is another argument), and perhaps Renew (yes, yet another argument). So let's try to roughly lay it out:
0 - Shield
1 - (global cooldown finishes) Penance
2 - (clip the end of penance to avoid the global cooldown) Flash Heal or Greater Heal
(Note: The global cooldown is likely down from 1.5 to the minimum 1 second with most gear)
To be completely fair, one would need to compare a full cycle, of probably 15 seconds (the shield debuff duration) or possibly based on the Penance cooldown. But even without doing that, it's simple to compare x number of seconds of the above kind of healing versus the same amount of time with a shield every global cooldown being spend on shields. Shields win. By far.
This leans on the assumption that the raid is taking enough damage for shields to be as effective as possible. In my experience, this is always the case. Always always.
So in my experience shielding is extremely effective. With ones tank-healing chains removed, what can one expect from one's raid experience?
- Casting a shield every global cooldown -- that's every 1 second -- with only rare breaks for "long spells" like Penance.
- Since old targets will have the shield debuff on them, one needs to choose new targets individually for every new spell. Every global cooldown.
Needing to choose "in danger" targets. Every global cooldown.
- Chosen quickly and wisely, shields prevent death and give the time needed for the slow one and two-second spells to pound on that green bar.
No "lolchainheal" intelligently picking targets. Instead, we have Prayer of Mending. Instead of a "green bar goes up" spell, it's a reactive spell that only goes off when a target takes damage. Thankfully whatever cooldowns it used to have must have been removed and it bounces like a maniac. It can be repeat-cast but it doesn't really work like a Chain Heal.. it's lifespan is really variable and it requires crazy attention (or an addon that I'll find) to use it most effectively and keep it bouncing around the raid.
- With no AoE-healing ability aside from one long-cooldown spell, Prayer of Mending is quite useful.
The more instant-cast abilities one uses, the more free for locomotion one becomes. This means that a discipline priest becomes even more effective when they can locomote to somewhere they will be needed the most. When I say "becomes even more effective" that means you will be doing it, because every little bit from every raid member matters.
- Also it should be said that the more mobile the healer, the more mobile everyone else they manage then becomes. This is a Good Thing.
- Now with this added mobility, viewing and interacting with both ones raid frames for healing/etc, and the playing field for movement, becomes invaluable.
- While a Priest cannot purge poison or dispel curses, they can cleanse disease and dispel magic. This function is often extremely important and requires AddOns to be as effective as possible. These are more instant-cast and therefore global cooldown spells. Also, these two abilities are from two separate spells.
Mass Dispel is unique to Priests. A strange "targetted-AoE" spell out in the playing field can be quite a shock to switch to from clicking on unit frames.
The main difference from most healers is that the Discipline Priest pushes hard against their global cooldown. They want to cast as much stuff as fast as possible. This requires the player to make extremely quick priority and spellcast judgments.
Instead of "my heal didn't get there in time", it is I didn't get there in time. This is why I said "player talent determines the outcome of so many situations."