[Kameron8]

And the main issue is for builds that NEED to hit the back because they are using a weapon that can be parried and riposted. So for Kensei/VA they are fucked regardless against a BK using this.

can confirm, am a kensei/va with a sword

Being forced to play into something like stalemate 24/7 makes things impossible, the damage you do is negligible compared to something like checkmate (which is guaranteed after stalemating to flatfoot).  The hard counter skill, Obscure, only results in you using more FP than the soldier while still being unable to get passed their front that turn in most circumstances.