Thanks for the input. Yeah, after reading your comments I went back and looked at videos from last year when I was playing a lot better and it seems like I was doing a better job of keeping the club face more neutral through the takeaway and backswing, which I would imagine is what is leading to compensating with a change in club path and the steep downswing. Definitely something I'll use next time I am at the range.
So he was using it to aleve back stiffness, which in turn helped his swing. But he also used it with his driver on par threes, where he was hitting a short iron. The rule seems to punitive. For us with this guy, if it came down to he can't play w/o doing this, we would rather have him play.
Thanks for the replies.