I believe that the ban of acetone came as a result of some pro from way back in the day soaking his balls in acetone to soften them up. (To increase traction?)
Acetone evaporates very quickly and I doubt it would soften a ball coverstock even with regular cleanings, as long as it was applied using a paper towel or other equivelant.
I keep acetone on hand to remove excess superglue from around the edges of fingergrips and to spot clean really stubborn gunk from the occassional filthy lane. I've never seen anything to indicate that it damages or modifies the coverstock in any way, shape, or form.
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ILBT!
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