The guy is a little round in the middle, but no more than normal. I thought that maybe he has too long a draw length. Could it be something he is doing as far as shooting form? I have done this a few times and I'm pretty thin, but only on rare occasion does it happen with me. My thinking is that it is a combination of a little too much draw length and stance. I think that if he faces the target a little more head on it will change the geometry enough. He may be facing too much sideways to the target.