It depends... you can drill a ball label, and it will hardly be affected by a PAP change (or unknown PAP) at all.

If the PAP changes through release changes or the like, it can have severe effect on a ball's performance, but it is hard to generalize. At least, the ball might do different things than before, and in the worst case end up as crap.

A personal story: a friend of mine used to have a PAP of 5" over and +/-0. He had several balls drilled strong (almost leverage), and he changed his release after coaching. The PAP went up by 1", now 4" over and still +/-0. Not much one would say, but those balls with the leverage layout now had the pin (relatively) closer to the PAP, and it was enough to make them migrate their PSA towards the pin axis, not the originally intended 90° axis to it. The result was a kind of strong pin axis setup that killed the balls backend into a smooth, rolly arc, with lack of hitting power. Effectively, half of the arsenal got screwed, esp. balls with a high mass bias which are more touchy with their drilling.
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DizzyFugu - Reporting from Germany

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