Dual Wielding attackspeed bugged

Dual wielding without any attackspeed scaling seems to be slightly slower while dual wielding equal weapons, but gets exasbarated the more less/reduced attackaspeed you get.
Here's a video example:
https://www.youtube.com/watch?v=VWRIsKg9gZ0

It makes it nigh impossible to dual wield skills that have %less attackspeed while DW, like Volcanic Fissure or Eartshatter, as it seems like every negative modifier gets applied twice or at double effective value.

https://www.youtube.com/watch?v=F2HWwCRGJFY