Minimizes stress cracks between pins and holes.  I personally try to maintain 1/2"  pin to hole distance and have a few balls with the pin in the ring finger.

I'd say if you're putting a recommended layout on a ball and the pin falls withing 1/4" of a hole, put it in the hole.  Just remember that drilling pins out needs to be done with a smaller bit than the ending finger hole size to prevent the bit from jumping.  I'd rather have it jump in the first hole than in the final hole...
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"A word to the wise ain't necessary -- it's the stupid ones that need the advice."  Bill Cosby
"Never argue with an idiot. They bring you down to their level and beat you with experience."

Tge pin is not a real part of the ball, so the area around it is more fragile to hard preasure then other parts of the ball.
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