I had this discussion with our shaman class lead about a week ago. It seems to work well for me and he has had no probLems at all healing anything so far
Stats: Haste. > Crit. > Spirit > Mastery. (of course int as well but that comes with pretty much any of the others)
water shield and earth living
Rotation: remember shamans are basically reactionary healers but this is a good way to go.
Earth Sheild first
(start of pull)
Earth shock the main target to slow the attacks and make riptide basically free
Healing wave/greater healing wave. (I'm still out on that one. I prefer to use HW as my normal heal but he says GHW is the better coice and it works for him. 60k heal crits)
Use healing surge as the go to for quick top ups
Natures swiftness and GHW macro or uses together for the oh sh*t moments
Basically when earth shock is up and riptide s getting low start at the beginning.
Don't forget about the mana regen you get from casting lightning bolt and helping out the dps a little too. I know it seems like you won't have time but with RT, ES, and earth shock on the target there is plenty of time
Hope this heps. If anyone else has some ideas I'd like to see them too. I'm always looking for different ways to heal
Edited, Jan 11th 2011 2:18am by FinalMeat
All tanks have the 20% attack speed and 10% physical damage debuff, so Earth Shock is a good way to waste 4k mana and a GCD every 8 seconds. Even with 3/3 Focused Insight, you're spending 1k mana and a GCD to buff your next heal by 30%. You get the same effect from Unleash Elements, with an extra direct heal, by putting 2 pts in Elemental Weapons.
Crit is generally a better throughput stat than Haste after you hit 916 haste rating (extra Riptide tick) due to AH and AA procs, plus mana regen from IWS procs. Your Mana Tide is based off spirit, so put it at a low priority at your own peril. I have around 1850 spirit right now and a few different trinkets in case I need more.
60k GHW crits? Let's assume I'm getting at least 15% from Deep Healing (+6% healing out, +15% healing recieved), use Unleash Elements and a Shock (30% and 30%), and have Earth Shield up on the target (15%). 1 x 1.06 x 1.15 x 1.3 x 1.3 x 1.15 x 1.53 (crit w/ healing crit meta) = ~3.6x modifier. That will get you there in pre-raid gear, but only once every 15 sec, and it takes 2 GCDs, a ~1.7 sec cast (assuming Tidal Waves), and hoping you actually hit with your shock to pull it off. In other words, it's way to unreliable for regular tank healing.
GHW is not more efficient than HW for regular amounts of damage (pending changes to GHW in 4.0.6), and HS beats out GHW under Tidal Waves due to the extra 30% crit. GHW does benefit the most from Unleash Life and provides the biggest snap heal with NS.
As for the OP, are you talking about tank-healing in a raid, or just healing the tank in a 5-man? Basic rules of thumb for resto shaman healing: keep Earth Shield on the tank, keep Riptide on the tank, UE+GHW and NS+GHW are good for high tank damage, so is recasting Riptide + HSx2. The latter has a good chance to get AH back up on the tank. TC is good for mana regen, especially if the boss has a burn phase (like Magmaw), but it takes 16% hit to not miss in raids, 6% for heroics. Miss too much and you could lose more mana than you get back.