Swipe is pretty useful in my experience. Basically if you swipe during a physical ability cast, the bar will complete but the ability won't activate. If you do it when no ability is being cast they won't use any cast abilities (physical or magic) for 6 sec or so, which gives you time to line up your global cooldown so you can get the stun from shield bash in.

Not 100% great but pretty handy from time to time.