Quick update: I did 10 shots with Madora with no buffs, and then moved to Power Stance. There was an immediate improvement in her damage with Power Stance as well as with Oath of Desecration.
BUT, I was only testing Normal attacks at first. So it might be the case that the damage-boosting things no longer work with skills, but only normal attacks.
Is that surprising? I could have sworn I read this somewhere already, in which case it's working as intended.
I'll see if I can find it.
Edit: It may have been the wiki. It explains there that stances only impact normal attacks and not skills (which makes sense since they can't miss, meaning the hit-chance penalty for the stance would be meaningless). This is wiki info from the original D:OS, by the way, suggesting it's always worked this way.
