Another thing about Durbin, he used different approach steps to modify his approach speed, taking 3,4,5,6,7 steps. He also used grip modifications to tune his release. He won tournaments using all these steps plus going to a semi or fingertip or a houseball drill when he felt like the thing to do. He said it was a lot easier using these techniques instead of trying to train his brain and muscles to do a bunch of different things. Kind of like the modern bowler changing balls all the time to fit the lane conditions.