I don't know if anybody else does it, but I've just now found I can do feint attacks by tapping a block during an LB attack to interrupt the animation in the first few frames. What I do is LB attack, then quickly hold down the RB to high block to stop the animation before the attack fully comes out. Then I can step back, attempt a takedown or hit with another attack.
It looks really awesome with boxing (LB+X -> RB interrupt -> LB+Y looks awesome as hell when it hits or knocks down. DEMPSEY ROLL!). Kickboxing (High Kick -> RB -> Superman Punch or vice versa, also Superman Punch -> RB -> Torso Kick) looks good too, but it leaves me wide open when I'm too far out and inadvertently interrupt a spinning back fist. Muay Thai is pretty horrible for interrupts so far since I haven't found a good initial feint with the style. I can step in with a feint knee, but there is too much downtime before I can attack for it to be effective.
I'm playing around with it and I've added it to the things I do online. I don't know how effective it can be against people swinging for the fences, but I figure it can seriously mess with people looking for a counterstrike or counter-grapple.