Restoration shaman - What is better crit or mastery ?

Restoration shaman - What is better crit or mastery ?

One of the more frequent questions regarding restoration shamans on forums is "What secondary stat should I go for - crit or mastery?", so let us take a look at the question.

I rely on my experience from the current content and since that is a 25man view I will refrain from stating anything in regards to 10man, or almost.

Now, there is two types of raiding 10man and 25man, but even when we separate these there is also the factor of how "hardcore" you play. By hardcore I mean are you e.g. atm. progressing on 2nd or 3rd hardmode or are you progressing on Elegon or Will of the Emperor on normal ? This may perhaps not appear to be that big of a difference, but they are since with the current gear levels you are forced by the dps requirements to push the number of healers as low as possible e.g. we had 5 on Gara, 3 on Spirit Kings and 4 on Elegon ("prefix" of the Energies not dealing dmg. when killed).

So an assumption would be "Since we are running as few healers as possible, then mastery will be the best stat since it in the previous expansion was thought of as the best stat during progression due to mana efficiency?", and with several theory crafters have calculated that it is around 70-65% that mastery overtakes crit in terms of throughput, and with progress people will end up there often, so therefore I should go mastery, no ?

I disagree. Mastery is a good stat and that there is no discussion about, but we have to look at mastery as a stat the in order to become effective will decrease its own effective value as soon as it becomes more potent. This might not look like an issue, but let us take e.g. Feng on HM during the fire where the raid is taking quite a bit of dmg., and you rotate your CDs in order to cope with it. The raid is on 50% and a CD is popped and ppl. are back at 75%, your heals until ppl. reached 70% was as strong as they could be, but now that ppl. are at 75-80% you healing decreases. You might say "But they are out of the "dangerous" zone now", well not really since they still require healing and since you currently no longer is healing as much as you could be your fellow healers has to pick up the pace thereby blowing more of their mana. 

My issue with stacking mastery is that you gear for 10-20% of an encounter, I am aware that people will be smashed below 70% more often, but with the passive smart healing from disc priests, WG and HST it will not be consistently "good".

Whereas crit. might "loose" to mastery when people are below 70-65%, but what you have to remember is that your raid will stay above that marker longer since your throughput from 100-65% is higher, and furthermore with you healing more for what will be the larger part of the fight your fellow healers should enter the "hard phases" with more mana thereby increasing your overall throughput.

That is the HPs side of it, but there is also the additional gain from Resurgence whenever you crit. which will grant you some more mana and while it might only be 2 or 4 more casts it will matter for when you are progressing.

Furthermore, on fights as Gara where DPS is tight, and even the healers have to push it then you will gain more from crit. since it does also slightly buff your DPS. 

Therefore I strongly suggest that you aim for crit as your secondary stat instead of mastery, and feel free to disagree and keep stacking mastery, and that will also make it easier for you to jump into elemental off spec and do dailies and whatnot.