Well, Erik
I'm kind of new but, if possible I tend to pour some of the shipping water out. I've not heard of this before. I know you can't totally control the waste in the shipping bag but, I think the idea behind separating the fish and not feeding it for a couple days is supposed to cut that risk. I can only recall loosing 1 fish so far after being shipped. I do use the drip method when a fish is shipped but, I also use it when transferring a fish to a different tank. It might be over kill but, I'm not in a big hurry these days.
JerryB