i have seen it happen, but not breaking into pieces...
a man in a house i practice at hit the pocket and you heard a weird *pop* . he started raising hell as soon as his ball came back: the ball had a crack all around the coverstock, and it was literally about half an inch wide in some places. the core held it together. the ball wasn't cold or hot (70* temps, season: fall) so the pro-shop bought him a new ball and drilled it for him.
it was columbia, and only a few months old.
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i don't care who makes it, how much it costs, or how sexy the ball looks. does it carry the 7 and level the deck? did i just beat you? aren't i clearing the heads with my $60 ball?
bring on the Lefty uprising!