From someone that owned three gas stations I can tell you that some of your post is wives tales. Our tanks were all monitored by a system that tells you tank temperature, and I can tell you the temp does not change much (less than one degree on a summer day) here in So.Cal. The tanks are insulated and buried, and the amount of fuel usually kept in the tank would make it very hard to get a significant rise in temperature.
The fuel also is filtered before it reaches your vehicle so pumping while a truck is dropping fuel is no big deal.
The vapor recovery system used on the pumps in So.Cal. would not be able to recover liquid in any significant quantity (if at all) because it works off pressure. You would need some type of pump (like the one used to pump the fuel to your vehicle) to be able to pull liquid back up the hose.
But if it makes you feel better do all of the above...
