Forward rotations in the pipe are rare, just because the slope usually forces you into a backwards rotation more naturally. You really have to rotate extra hard to make it all the way around onto your feet again. But yeah, I saw a bio in the pipe a few years ago, and yes, it was really really sexy and cool.
Another reason why you dont see them: Pretty much just a blind landing, so way to really tell if you're going to deck out or not. Really really risky...