Long time shadowy lurker, first time poster/caster (well not counting my add to runners looking for Johnsons)

The Smashing Blow adept power does not have any prerequisite for Killing Hands.
However in the barrier part it says that barriers ignore stun damage...
So the question is if want to use this power do I need to have Killing Hands active as well...? Any other tricks to turn unarmed stun to physical to circumvent blowing a PP on Killing Hands just for that?
2 friggin powerpoints to become Kool Aid Man is unkoolly impenetrable ... And the Shark Mentor Sprit that gives killing hands for free comes with its own unique set of.... mmm.... hurdles...
Gratuitiously violent and shamelessly unrelated plug that if anybody has a SR PBP game with open spots, I am looking for a game...