he's wrong!
google octane ratings
if your vehicle requires regular, then use regular
instead of going to a premium gas octane, use something called
a FUEL stabilizer
that will keep your fuel fresh in the tank for
up to a year
http://toolmonger.com/2006/12/05/finds-sta-bil/
i use this for storing my motorcycle and small sports car that i use sparingly when i don't need to lug my kids w/ me