First off apologies for the long ish post but it includes my reasoning for crit over haste.
I have 2235 mastery that says 20% how is your 1190 giving you 36%?
Kamugi isn't wrong with this statement as I said in one of my original posts Disc priests can be spec-ed pretty much any way and get the job done it just depends on what you expect from your spells.
I personally didn't like the haste mastery build because lack of crits meant more healing was required from bigger heals with less down time and mastery wasn't getting used fully unless you either shield spammed or PoH spammed.
As for our crits being mostly overheal that depends on how much you expect to heal, In most situations I don't worry about over healing as I generally have very little of it take for example this log from shannox heroic 10 man:
http://www.worldoflogs.com/reports/w...?s=3506&e=3785 I over healed 17% on Greater heals that crit at 52% compared to 20% over heal on PW:shields.
The way I look at it though in terms of haste vs crit is: correct me if I am wrong on cast times they are complete guesses.
Haste stacked Priest: A single Greater heal cast non crit with high haste will cast at around 1.5 seconds including borrowed time and will heal for a static 30k.
Crit stacked Priest: A single Greater heal cast + crit with a cast time of 1.8 ish including BT will heal for 60k + 25k DA.
So a haste stacked Disc priest will have to cast 3 times to equal a single heal from a crit stacked priest and the DA shield being almost equal to a PW:shield reduces the required healing next time the tank is hit so over all high crit equals less casting required, less mana required, and less haste required.
Again though Crit is still RNG and you are not guaranteed to crit on each cast but if you have at least 18% unbuffed and the 5% + 3% crit buffs in raids then on pre shielded targets your crit rating will average out to above 30% on single target casts which I find to be good enough to allow me to have the build that I have.
Other then Shannox where I fallow the dog tank out into the middle of no where I generally cast more raid healing spells and shields to assist the second healer I have never been one to focus solely on a single target and generally tanks don't really require constant healing anyways.
I should make note though in my current gear over powered as it is as I said above I have 11% haste, 20% crit, 20% mastery but when raid buffed with all the bells and whistles ( weakened soul on target, inner focus not included ) I have 16% haste, 38% crit, 20% mastery so it's not like I am lacking any stats by choosing a crit based build and at most I am losing around 5% haste ish which is what 0.3 cast time from 16% to 21%.
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