Chang wanted to make sure the cue ball was exactly where he wanted it to be. To do that he had to see it from the end of the table where he was standing. He couldn't reach the spot with his hand so he used his cue to maneuver it into into position.
I was stationed in Cu Chi Vietnam 69-70, but didn't see it much. I was a radio telephone operator (RTO) for awhile, carried an M-79 grenade launcher and an M-16, but mostly I was a tunnel rat.
Great 10 ball match between Van Boening and Antonis Brabin, .
They were calling 'ball and pocket'. 9 ball on the break doesn't win. Helps to reduce slop. My kind of game.
I agree. The myriad variations of a pool stroke preclude the usefulness of any 'device'. As I said earlier; dedicated practice is what turns a 'banger' into a expert.