Here's one from Idiots' Corner, so please bear with me.
This morning, and by no means for the first time, I wrecked an inner tube after pumping it up with my track pump. The problem occurs when I try to release the pump tube-end from the inner-tube valve. There's quite a bit of pressure locking it on and it needs a good tug to get it off. This makes me feel I'm doing something wrong. Am I missing a trick, or is it just a case of holding the inner-tube valve steady while I yank the tube-end off?