Duke's carry is phenomenal because his release is one of the absolute purest in bowling. Notice the lack of muscle on the downswing, the relaxed grip the whole way through, and the very open hand position when his fingers come out of the ball. He gets the thumb out quickly, then the fingers almost as quickly, and just lets the ball do the work for him. Pete Weber is the same way as far as the actual release itself goes when he's bowling well (different hand position, a LOT more axis rotation, but still the same idea, very relaxed, open hand, no hit at the bottom of the swing). You can tell when PDW's struggling because he starts trying to make the ball hook and carry by grabbing it a little at the bottom, and that's when his ball reaction gets over/under and his carry goes down. Be kind to the ball and the pins know it.
WRW's carry on the other hand can sometimes be poor because of his very forced, end-over-end roll. He uses a very unorthodox release, he really comes up a lot at the line with his whole body, with a very muscular jerking motion from his arm to create extra ball speed, but he's just so amazingly accurate that he still throws a ton of strikes. You can see a great difference in the way Duke's ball rolls down the lane compared to WRW's.
