20 years ago I drilled balls for a guy here in Houston, he used 1" reverse and 1" left, still uses that pitch today. Man could he get some serious s$@#& on the ball. He won 1 PBA Regional title, reverse block, scores really low, only two players in the whole tournament are plus, him and Mark Williams. Alan average about 225, gettin' it off the right gutter. AWESOME. He had the Houston City Record of 850 something with a White Dot, before urethane.
The most extreme pitch I drill regularly is 1 1/4 reverse and about 1 left. This guy has about 5 1/2 spans, long, slender hands. He doesn't need all that pitch, but he is convinced that it helps him and he likes it.
BTW, I just added reverse pitch to my thumb, I'm all the way to 1/8 reverse and 1/8 left, oh man do I fly out of this thumb pitch. Lots of white tape!!! LOL!
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Mike Austin's Precision Pro Shop
Houston, TX
Drilling and Tech Advice BirdDogbowling.com
Driller to many "Stars" and Tony Melendez too!