It seems like more and more are picking up on combat as a viable PvE spec, and one of the main drivers for this are the spec's AOE capabilities. However, it occurs to me that few have actually looked further into the AOE rotation. Surely, it's just about popping Blade Flurry and go to town while Eviscerating everything? Instead, I asked a simple question: at what # of adds does Crimson Tempest become a DPS increase?
Since I've not found any current research on the matter, I took Excel for a spin to see if I could come up with some estimates. Here's what I discovered:
Eviscerate: I calculated the damage based on the actual Eviscerate plus 40% of its damage on any number of secondary adds. Presuming Deadly Poison is up on the current target, I also added the 30% chance of Eviscerate proccing Deadly Poison Instant.
Crimson Tempest: Crimson Tempest Physical is the damage it does on hit, while Crimson Tempest Bleed is the second part of the spell. Unlike Blade Flurry, this spell has the default 30% chance of proccing Deadly Poison on any target it hits, so I added the average amount from that. Finally I added the chance of Deadly Poison Instant on current target.
(You can download the spreadsheet here: https://dl.dropboxusercontent.com/u/...ontempest.xlsx)
Bottom line? Crimson Tempest should be maintained in situations with 2 or more adds.