nice question.. I will be interested in the replies.
I think pin distance from the PAP is the primary and most important decision when deciding what you want the ball to do. Degree to VAL and degree to MB are secondary.
From my experience. A ball is best drilled with layouts that go along with the balls designed reaction. Cant make an early heavy hooking ball a super skid flip ball and you can't go the other way.. (sometimes you can with surface mods and exotic drillings)
Also, I think I have figured out for me that it is best to drill most of my balls pretty similarly and let the design of the ball do what it is going to do. Example.. bad experience with a cell.. wanted a earlier, smoother, heavy hooking ball.. so I drilled my cell pin down and 45 deg.. didn't work.. I think it was just too much of everything.. I should have drilled it pin above bridge, 5.5" to pap, 60 deg mb like all the rest of my stuff and let the Cell's core and cover provide the smooth and early hook.
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16-17 mph,350 rpm,PAP 5 1/2 x 3/8up, HighGame 300 x 3, High Series 782
Book Average 215 / 205,PBA Xperience ave180