This was originally posted privately on my guild's forum. It was written back in BC.
Guys, I can understand when some people don't know about this.. but this should be common knowledge for healers. Perhaps at some point this stacking wasn't true, but it's true now.
Threat management is one of the most important tools in a raid situation. It's just as important as well-placed, fast or large heals.
As a healer, it's my job to make sure people stay alive. If I drop a totem or I pop heroism it's not always for the benefit of DPS. I do go out of my way to off-heal outside of my assignment and sometimes I do pull aggro on purpose.
"What?" you think. Think I'm crazy for pulling aggro off the tank? For beckoning an add to me? You think resto shaman have no aggro-dumping ability?
On one of the last pulls to Morogrim Tidewalker, our main tank pulled heavy threat on too many mobs at once and nearly got smoked. I can do this because I can pop a hard double-heal because of some macro voodoo I have with Nature's Swiftness. I intentionally healed heavy and pulled aggro on one of the elites.
It's no problem, I kept healing. The mob I pulled was a melee mob, and I saw it charging at me. I could know this because I was at extreme range. This gave plenty of time for both me and the other tanks to react.
I knew I pulled aggro because of an AddOn. DBM (Deadly Boss Mods) can do this for you, otherwise check out BanzaiAlert.
Again because of good AddOns and experience I could time an instant action in concert with a non-instant action so that they could both act with only one global cooldown. That's a 1.5 second savings.
I do this because of Quartz and a cast bar that calculates the window of opportunity that lag creates. Yes, a bit of lag is actually a good thing if you know how to use it.
I timed what could be my final heal with threat reduction. Yes, we can all reduce threat. Using trinkets. I have three and one is cycled automatically when it's on cooldown so I usually have something ready.
The fourth trinket is a fwcking awful chain of quests through level 60 endgame nonsense, and the fifth is a rare drop from a level 60 endgame raid. So three is all I have for now.
I popped a threat-reduction trinket, and since it wasn't enough I also popped my threat-reduction cloak.
This chain of events was enough to dump aggro and have the mob run all the way back to the group of tanks. At this point the other tanks had picked up their mobs and the other healers had the healing situation under control.
Threat > positioning > timing > speed > +heal
Who cares how much you heal if one of your party members pulls aggro?
- Yes I can keep the tank up, but so what if half the rest of the raid is dead too?
Who cares how much you heal if you're not standing in the right place?
- Line of sight issues and positioning to off-heal is important. Did you know that you generate significantly more threat when you're within easy striking distance than when you're out at range?
Who cares how much you heal if you're not healing the right person at the right time?
- Yes, keeping the tank up is great, but keeping CC and AoE up is also a good idea.
Who cares how much you heal if you don't heal fast enough?
- This isn't always spell haste either. Nature's Swiftness ftw.
Oh, and coordinating heals is also a good idea. Some people like the healbot AddOn. I have it so that others can benefit from it, but I don't display it myself. I use intuition. It's faster. =)
Remember, threat is the most important thing to know about..