I think the forums are lagging, so if this gets double posted, blame blizzard :P
... at the last few pages in this thread...
Mastery does not 'beat' haste in any situation for HPS. Anyone that thinks so is clueless.
Mastery will effect rougly anywhere from 100% to 30% of your healing, with realistic situations being in the 40-60 range. For comparison, at 40%, mastery is eqivelent to Crit in HPS and HPM. There is no refuting this unless you are truley clueless.
The only stat that can even remotly compare to Haste, (and that is not Int) is spirit. Spirit will give extra mana, that is all. In order for spirit to effect healing, you need to either be running out of mana (increases total healing via high HPM spells), or you need to be able to upgrade from HL to DL via the extra mana (which practically requires you to not be already running OOM).
The best situtaiton for spirit is a 1 target healing fight, something that is not even all that common in 5 mans. Under these situations, if you A) already have enough mana to last the fight, and B) do not have enough mana to replace every HL with a DL, spirit will grant you the the capability to gain HPS via extra Mana spent, which is recovered via the spirit.
For some numbers I chose at random that are close to a starting raid build, you would get roughly 6600 HPS from upgrading HL to DL in this fringe situation that compliments spirit. The cost of this is aprox 5600 Mp5. You can recover this with 12,500 spirit. To cover this with Haste, you would need roughly 11,000 haste. So in this contrived and flawed example, using HL with haste is still more HPS then using DL with spirit. We did more total healing with spirit via more total mana, but at a lower rate then if we used HL. The cost of using haste to reach this HP was about 4400 mp5.
What does this tell us?
Choosing spirit and not using DL will give you extra total healing via extra mana, with no increase in HPS
Choosing spirit and using DL will give you extra total healing via extra mana, with less of an increase in HPS then haste.
Choosing Haste and not casting HL faster will give you extra total healing per mana from Holy Radiance, with an increase in HPS.
Choosing Haste and casting HL faster will give you extra total healing per mana from Holy Radiance, with a larger HPS then spirit with DL.
In both cases haste increases HPM and HPS. Spirit will only increase HPS or HPM at your choice. If we consider an AoE situation, it makes it even more favorable for haste.
Haste vs Crit/Mastery for HPM.
Its obvious that crit and mastery are terrible for HPS, so lets check HPM. 1% crit is roughly 0.5% more HPM. In a 34% mastery condition (HL raid healing with LoD and HR), HR takes up ~20% of our healing. With 1% haste, the HPM of HR increases by 1%, or a 0.2% total HPM increase, while Crit would be 0.5%.
So in this case, haste incresed our HPM by 40% of Crit, and also increased maximum HPS by 200% of Crit. Then we have to consider that 1% haste is 71% the cost of 1% crit, and we just multiplied our haste results by 1.4x, granting us 280% HPS and 56% HPM of what Crit would have been.
While I assume a low mastery rotation, I also assume that all mastery is 100% used. 1% Crit results in 1.25% mastery for us, which results in 0.425% extra HPM and HPS. Haste compared to mastery: 65.6% HPM and 329% HPS.
Now, the entire point of this is pointless unless someone can equate the value of mana, and I see many people saying "Don't use haste, it costs mana, use this other stat and cast DL". Haste will increase the number of efficient spells you can fit in the boss fight, both raising HPS and total healing if you have enough mana to use HL the whole fight, which you should. Using Crit/Mastery/Spirit with HL when you don't OOM using it is less total healing then haste.
Upgrading those to DL with Spirit is still less healing per time then haste. But now you are spending more mana per healing, and more mana per second. As I said before, this is only even remotely worth it for Spirit, which gains almost enough mana per stat to allow DL to provide substitutes for HL for a net gain. The HPS gains of Crit/Mastery on DL are less then Haste on HL, meaning that as haste goes up, you can replace DLs with HL, HPM gains of Crit and Mastery also go down moving to the lesser HPM DL.
If you do not have enough mana for a fight to use HL+HS+HoPo dump, you need more gear, or your players need to stop messing up.
TLDR, if you want to try to spam the big heal like in Wrath, use Spirit + Mastery + Crit as your secondary stats. If you want to maximize Healing per Time and Healing per Mana, use Haste + Spirit for Single Target, and use Haste + Crit for raid healing.
Edited by Faelyne on 12/22/2010 1:42 AM PST