SystemicAnomaly
Bionic Poster
Gritty hard courts will fluff up any ball.
I play on the same courts with various different balls. It is my experience that the extra duty US Open balls fluff up more than Penn balls (Champs and ATP) when playing against certain players. Those guys specifically complain about the Us Open balls fluffing up -- but we never have much of a fluffing problem when they are not playing.
Perhaps the humidity in Florida has a fluff factor effect.