I fail to see how this is proof of the soak being helpful? Perhaps he had been keeping proper humidity levels throughout the duration of the shed cycle and that was why the snake had a good shed? Seems a matter of coincidence to me.
I own one Ball Python. Personally, I do not do anything differently when it sheds. I am mindful of the fact that the environment I provide is adequate to aid in proper shedding. My Ball Python sheds perfectly nearly every time.