Hmm I've always been a 1-click man...man just thinking about it, basing all this off of some dang fuel pump's auto shutoff doesn't seem that dare-I-say accurate. Does anyone know how those work?
Found something:
HowStuffWorks "How does a gasoline pump at a filling station know when the tank"
Ooh there's a hole in the tip...hmm....
Are you using the same gas station?