Personally, I think that de-oiling a ball every 50-75 games is pretty excessive, especially if you clean your equipment after each outing. I tend to take mine and put them out in the desert heat once a year, and have not seen a loss of reaction for several years now. As for the little voids where the oily worms were in your bowling balls, I've never heard of this before, and personally, think it's nonsense. Just my opinion.
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