You are left nekkid of any stances once PB wears off (must DK/BS without stance +effects). This is understandable, but in PVP it's been giving me some grief.
Somersault gives a very short PB buff that I often forget about, ends up causing me trouble.
There's so much CC in PVP that when I'm trying to use an ability but can't because of no stance (which is the case when PB falls off) my first assumption will be that I've been stunned/slept/pacified, not that I'm stanceless and need to go back to DK/BS. That lost precious second before realizing this is very precious. And lost. :<
Just something I need to get use to.