... Sanding my thumbhole is not much of an option, since my thumb swells a lot, at some point, most of thumbhole is lined with tape. If it wasn't so thick, I would consider using only white tape for texture, but it's so thick sometimes I'm caught between pieces of tape for the right fit. ...
I didn't suggest sanding so much it would change the size. Just swipe or two to change the texture and remove the tackiness.
If you must use that much tape, I'd suggest you have a serious thumb problem: it sounds as if it's not drilled or sized properly for your thumb. If you have pieces all around the nside of the hole, it may not even be shaped correctly.
No one's thumb swells and shrinks more than mine does during the course of bowling, summer or winter. I may add or remove 1 - 2 pieces during a 3 game block. In a 5- 8 games block, that could happen 2 or 3 times and the number of pieces will grow to 3 - 4 pieces. But this is just in the front of the thumb hole, not all around.
I have to give charlest a +1000 for this comment.
If you havent read the latest BJ - there is an article with top 10 tips from top coaches.
1 tip was proper taping of the thumb hole.
not using any or not using tape properly causes improper grip pressure (which in turn can cause excessive swelling)
I just did a grip check and found out my grip wasnt right, you need an experienced driller to be able to check your span, flexibility of your digits, proper oval of thumb if needed.
HUGE change in my release and ball motion, eye opener for sure.
