In the early to middle 60's when the Family Billiard program, which Brunswick sponsored, Mosconi was the main Exhibition person. He ran a hundred balls every time I watched him. That was at least 10 times. He wanted brand new felt and unused Centennial Balls for his play. He did not use the SLIP STROKE all the time. Mostly used on his break shot. Earlier a poster said it was difficult to "Slip" being down so low on the cue ball and I agree. Some of his Trick Shots did require a tremendous stroke and his "Slip" was flawless. Of course the Masse' required a tight grip on the butt with no "Slip" there.