Currently it seems that, if the knobs refinement (the head one, that makes you attack twice) procs on the first hit after a perfume proc (the shoes refinement, that also makes you attack twice after suffering a crit), then it just replaces the first one, resulting in only two attacks, as opposed to three (which should've been the case, considering both procs) and therefore wasting a refinement completely, since the effect would have been the same without the knobs.
I cant confirm right now if his issue also exists between those two the stun refinement (piercing) as well.
As long as the refinements seem to apply only once in a fight, it would make sense to allow the procs to stack or, at least, to prevent a double attack to proc in the middle of another one, and thus guaranteeing the full effect of every proc.
Edited by ConnieLingus, 30 April 2016 - 16:24 PM.