Shouldn't pitch be completely independent, based on the bowler? DP said that he uses 1/8 reverse, while Nollster, who has a very high backswing (but lays it down very smooth) has a great deal of forward pitch in the thumb. Pitch isn't based on the swing, it's based on the bowler. Not to mention you have to discuss span as well, as 1/4" forward in the thumb for someone with a span of 4" would be comfortable, while someone with a span of 5 1/4" and that same pitch would think that it feels completely different.
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- Andy