AS Annikan said, thumb location influences the #1 PP. However, a long time ago (6 years or so), I tore up my left thumb pretty badly. So I cannot put my left thumb down the top of the shaft anymore. I use a classic 10 finger BB grip, with the left thumb on the right side of the grip. I have round this makes PP 3 and PP4 even more critical in terms of maintaining the right amount of pressure.
Obi WunPutt
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