I can't imagine why someone would want a different "feel" when picking up a spare ball. The whole idea of a plastic ball for spares is that you can use your "normal" release and cover fewer boards (i.e. go straighter) due to the low friction coverstock. A different span/pitches (in my opinion) in your spare ball would result in releasing it differently, therefore introducing some unneccessary inconsistancies into your game. If you like a shorter, more relaxed span or more reverse/forward in your thumb pitch or whatever, fine, but do it to all of your equipment, not just a spare ball.
S^2
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The perfect qb/receiver combo in Miami:
Ginn & Juice
(Ted Ginn Jr and Cleo Lemon)