I am tracking my mileage on Fuelly, which breaks down the percentages of highway versus city driving.
I'd have to agree with Vman that I do well BECAUSE I drive only stop-and-go surface roads, with only a couple of long stretches in my 21 mile commute. I couldn't get anywhere near the results I do if my commute was all highway. I have many opportunities for EOC, and then a couple of P&G opps on the straight stretches. I don't see it as cheating, I just take advantage of every opportunity I can to save fuel. Every driver has a different car and commute, and we all need to customize our cars and driving habits to the best fit for our particular situations.
http://www.fuelly.com/driver/cowmeat/festiva-2