I never questioned his skills at all, he is clearly an accomplished musician. I won't be eating any words. I just find his use of elbow and palm absurd and when I saw him do it, it lost all credibility. In my view, I don't see how it added to the piece and I think its purely for show, which ruined it for me. The drummer using the other end of his drum stick to tickle his cymbal was also frustrating.
I mean, if I was watching Herbie Hancock perform a piece and half way through he wolloped the keyboard with his forehead, I would assume he was having a fit.
If it wasn't for the pretense, I would have found it wholly credible. But as it is, it is far too like a Mulligan and O'Hare sketch.