I appreciate the unexplained drops in performance are tiresome.
I think, the most notable obstruction our developers and QA have encountered is being unable to replicate these issues internally.
It would really me out if you could add your information here:
http://forums.fatsharkgames.com/t/fps-drops-stutters-and-your-dxdiags/31170?u=fatsharkjulia
I will send out a reminder internally that performance-related complaints are still rampant.