Though I'm still inexperienced (only drilling my own balls), it seems to me that there are four distinct areas of ball drilling - fit, layout, drilling, and final adjustment.
Fit is a definite art rather than science. Too many subjective variables to fall into the realm of science.
Layout is more of a science for me. I simply look at what the ball is designed to do, make a decision on what I want the ball to do on a certain condition, and then make my best estimate of which layout will do that for me. Since I started using Mo Pinel's Dual Angle Layout, I have much more confidence that the layout I'm using is correct.
Drilling is a definite science. It's just a matter of getting the pitches right and putting the bit on target. Precision is the key.
Final adjustment is also an art. Again, so many subjective variables, but getting the thumbhole "just right" takes patience and skill. I'm finally getting better at my thumbholes...I only need to use a minimal amount of tape to get the perfect fit.
--------------------
A flute with no holes is not a flute, and a donut with no hole is a danish.http://averagebolwersballreviews.com/
