Yes, the track/PAP can move over time, and this can cause big trouble concerning ball drillings - especially when you have a strong pin position (3 3/8"), a PAP shift can totally ruin the ball recation because the ball migrates to a different PSA - even on strong MB balls. It can, for example, rotate around the pin axis, not the MB axis that is 90° to it. The ball reaction can be weird - a friend of mine "suffered" from this recently, his track moved down from about 5" over and +/-0 to 4" over and +/-0.
I recognized the weak back end and poor finish of his strong equipment, including a NM, BWS, Domination, LevRG, so we did some PAP measurement and taped the balls' relevant axis' to see what happened. And - through the lower track/higher PAP position - some of these balls with a pretty strong drilling migrated towards the pin axis!
After consulting our pro shop of trust, the only solutions had been plugging and re-drilling, or punch up new equipment. balance hole tricks would not be enough anymore.
Luckily, some balls still "behaved" well (those with a weaker and high pin position), but the NM had to be sold, the LevRG with low mileage went into the basement for better times and a new Cell with an adjusted drilling came along - and this ball (which is an amazing piece, BTW) finally behaved again as it was supposed to.
Track movement can be a serious thing. Better check your drillings and axis migration
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DizzyFugu - Reporting from Germany
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