probably because, Like Riddler pointed out, the Deadly Wind barrel uses freak inserts so the actual carbon fiber portion does very little in terms of affecting the flight path of the ball.
Hence the bore kits. I'm looking into one for the Stiffi so I can run field tests at extreme. Nothing says results then an actual game. Range work is one thing but when you get it out on the field, it better back up the range data. lol