It could be a range issue like you said.
On the spark phase I pause rotation with like 3 secs left of the new sparks spawning. So I always have the runes needed for a pest and than 1-2 obliterates with blood tap. I also usually try to pool like 50 rp for some frost strikes as well.
The reference number you were asking for :
I on average going into p3 (burn phase), pull an overall dps of 164k. So I was short by about 20k. But it could just be the melee range issue
Sent from my SAMSUNG-SGH-I717 using Tapatalk 2