I'd have to agree with Charlest on this one.
With the scenario you give, I 'd tend to picture Bowler "A", as being a slave to pretty much, one section of the lane......though he could play that one section with an assortment of different pieces. He might still suffer some serious carry issues nonetheless.
Whereas, Bowler "B" with his assorted release changes, would most probably change his hook shapes, which in turn might have him playing in some virgin, unused oil, and increase his carry percentage as well.
True, enuff....Bowler "A" could accomplish the very same thing by going to a different ball....I just think it would take him a frame or two longer, to realign himself to the pocket, and attain that good carry, all over again.
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Duct tape is like 'The Force'. It has a light side and a dark side, but it still holds the universe together.
Some days you're the bug some days you're the windshield.