Fuel Grade Shell Game. Take a look at http://www.fueleconomy.gov for listing of the manufacturer's reported fuel grades for each model. Site is run by Department of Energy. You should also be able to view a hardcopy pamphlet at the dealership but it does not list all models. For example, the 2003 pamphlet shows Escalade using regular gas. So, GM is telling the Feds that regular gas is the design fuel, even when many can't get by on anything but premium or regular plus booster plus carbon cleaner. That's even if we use best source regular and travel hours at 70+ every week.
So, how can our reality differ so much from what the manufacturer certifies to the government?