Consecutive posting. I'm merging this post with the one before it.
Originally Posted by Acroanidd
Over 2.5 seconds you hit 5 times meaning that each hand swings at .5 seconds. This is only slightly faster than dual fast. While Dual Fast with just SnD up my weapons were ~ .75s. The catch here is that these 5 attacks cannot proc sword spec procs or CP. Now if someone hits Heroism while you are using Killing Spree I could almost guarantee a loss of potential DPS.
I would possibly figure that putting that one point in Imp Poison to gain another 2% IP Proc might actually yield more damage.
I presume Killing Spree is considered a special and your analysis doesn't take into account the increased miss rate you would get from white attacks. In any case I tried it out with the setup I posted above and speccing out of KS to put the point into Improved Poisons (or even another point into Relentless Strikes) shows as a net DPS loss on the spreadsheet. I admit, however, that the situation might be different with higher hit rating and faster weapons.