> Now don't hold me to the 10 to 20 as I have read this several places but don't know the exact figure but do know it works out about that way.

Hard to imagine it could be that much, since only 10% of the fuel is alcohol, i.e., your numbers suggest one could get better mileage (20%) if you just didn't put in the 10% ethanol and instead only put in 0.9 gallons of gasoline instead on a gallon of 90/10 gasoline/ethanol!