yea, I'd say its something with your finger holes.. Maybe being a bit too tight...
I know when leagues start, my Thumb will swell up like a mofo... Almost to the point of where I cant get my thumb into the ball... Hence why I went to Switch grips. But it only happens during leagues for the first week or so..
After that, if i bowl like 4 games, take a break, then goto bowl some more, yes, my thumb does swell up...
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