Hello, I couldn't find a topic about shadow priest reforging on Sinestra, so this is why I made on. My guild have been progressing on Sinestra for a while now (a lot of hours spend in total), however none of the wipes are caused by low dps, but mostly by bad orb kiting or healing issues. However since I am usually getting some sweet WoL ranks I wouldn't mind maximizing my damage potential when we manage to kill her. This is 25man btw, so there will be less orbs targeting me.
I don't have any math to back this up but I am going to assume the stat priority during the time window of the haste buff would be something like this (especially considering that a big part of my damage will be mind sear): haste (until gcd capped mind flay) > hit (until cap) > mastery > crit > haste (after mind flay becoming gcd capped).
Haste: Stacking haste until mind flay has less than 1 second cast time seems to be an obvious choice simply because how well haste is scaling with an additional 100 % haste. Adding additional haste after this point seems like a waste considering that there's little movement involved in P3 except if you end up having to kite a twilight orb.
Hit: Well, I am quite unsure about this one. Losing a gcd on Sinestra in p3 is a huge waste of damage simply because of how much damage 3 ticks of mind flay is, and it's always good to play it safe. On the bad side moves like mind blast plays a very little role in P3 and the damage from sw :d is neglectable.
Mastery: Considering all the damage sources that scales with mastery goes up in P3, and that you can almost certainly maintain a 100 % empowered shadows during Essence of the Red, I am only going to assume that on this fight specific mastery is superior to crit. Mind sear also scales very well with mastery, making it an even more favourable stat.
Crit: Well there is nothing much to say honestly. Mana is not an issue at all, so less mana gained because of lower shadowfiend uptime doesn't seem like a loss at all. Shadowfiend damage, non-orbed mind blasts and shadow word: death are the only abilities whose damage isn't modified by mastery and haste.
The shadowfiend wont be affected by the 100 % buff during P3, so its damage will be relatively low. Casting mind blast non-orbed will be a dps loss because mind blast will be gcd capped, and the orb generation will be incredibly high anyway. Shadow word :death will be a dps loss to cast too, because it will be gcd capped and with all the damage going on anyway it also seems like a quite dangerous move.
I am guess mind flay will be gcd capped at this point (assuming you recieve DI):
2.163 - 1 = 116.3 % additional haste
I realised you needed 2.33 haste in order to get a 1 sec cast mind flay, that means 1.33 aditional haste.
1.1163*X=1.33 <=> X=1.1947 which means 19.47 % additional haste.
0.1947 = x/12800 <=> X=2492.62 haste rating where 128 is the rating need to gain 1% haste.
So 2492.62 seems to be the magical number. Well now I know this, but I still don't know how I should prioritize stats like hit, crit, mastery and haste (after 2492 rating). Any of you who can assist me with this issue?