Couldn't disagree with this more. Do tell, if you would, how this can cause more problems for the snake?
With my corns, if I handle them three days after feeding I can almost always guarantee that they will poop for me while they are out. I will wait for the muscle undulations near the vent, hold the snake over the toilet, and then flush when they are done. You could say that my corns are somewhat "toilet trained." LOL
So do you just hang out in the bathroom with them?
In some cases, at least with ball pythons, it's advised against soaking them prior to a shed, because too much soaking can leech out the essential oils under the old skin, making the shed worse, rather than better.