I've also wondered. He swears by it... his grampa swears by it... there must be something to it.
Theory 1: The 1 ball wants to back towards a corner near the breaker.
Maybe the airborne cue ball gets out of the way so it can do that, otherwise it'd kiss the CB.
Theory 2: It seems like it allows some control with the cue ball using any amount of topspin.
The cue ball rebounds backwards, lands, then whatever topspin is left on the CB fights
against the tendency to roll back towards the kitchen. The result is it dives forward and then dies.
If you had topspin without the backwards bounce, the CB would be going wild.
So this method allows you to hit hard without stressing out about hitting dead center ball.
Theory 3: It looks cool and strikes fear into the heart of the opponent, making even 17 mph breaks
look like nuclear strikes.