Possibly good advice, although I can't confirm or deny any of it.
My opinion(s)...
1) If it's underground storage, I can't see any temp benefit
2) a) There are filters (should be
) in place for this filthy problem
b) Just how long should you wait for the "stirred up" content to settle (a several thousand gallon tank would take x period of time)?
3) Most modern vehicles have a vapor recovery system in place in the fuel system...but...I would have to admit the chance of condensation in your tank would most likely be lower with a higher level.
4) The vapor recovery system is "sucking" vapor that is present in your tank already and is preventing "smog" from unburned HC emissions venting your tank into the open atmosphere...any container that is taking on liquid is purging a gas, as it is being filled. I doubt that it helping speed up the refuel process ala CART racing
...finally, the % of ethanol in fuel is "only" labeled IF it contains MORE than 10% (although this may vary from state to state)
just my $.02
