Does your calculations factor in Armor Penetration and Cloak of Pain and Gore? Remember gore gives you like 6 seconds of 100% Armor Pen... follow with your biggest melee attacks, like ravage and massacre... Deadly Throw is also a big damage ability too. Force Scream if you shoot right auto crits, etc...
Not sure if this matter, Massacre has a cool down of instant and can be done on the run as well.
Calculation was from parser, so no calculation.
And yes, every time I popped gore it was either paired up with Berserk Massacre spam with a Force Scream at the end, or Ravage > Scream with a Massacre right before Gore.