3 things to check that come into my mind:
a) pin position on ball.
For a high tracker, a very high pin (more than 1 " above finger holes) can result in a thumb hole position that gest it very close to the track.
b) wrist poistion
If you bend back your wrist, consciously or unconsciously, the track might move higher than usual, aven between thumb and finger holes (like a full roller). Concentration, some wrist training or a wrist device might help.
c) Finger pressure and finger grips/holes
Finally, with an uneven pressure of the fingers upon release, the track might move higher, too.
Some background... A friend of mine had the problem of clipping his thumb and even finger holes on just 1 ball some weeks ago, without a clue why. The ball reacted erratically, and carry was so so out of a sudden. Great riddle.
The solution (we hope it is!) was simple and complex at the same time: His middle finger hole with power lift grips had broken in some time ago, and he fixed it with super glue. Some small pieces of the coverstock must have slipped between ball and grip, and the superglue "baked" them into a small hump just under his grip point of the middle finger. the result was un even pressure, and a lack of ring finger power. this shifted the track almost 1" towards the thumb and caused the clipping (it even hit the finger holes sometimes!).
The ball is to be refilled soon, but this seems to be the cause for the troble.
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DizzyFugu - Reporting from Germany
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