Light right foot - true.
I get 55 mpg (that's per UK gallon*) from my 22 year old Toyota Corolla on a long journey (my definition of long in the UK is "more than 200 miles"). On 2 occasions I did precise mpg tests, both on journeys of about 220 miles but to different destinations. 55.7 on one trip and 55.6 on the other. In both cases I drive as described by Groit.
As an example of how speed affects fuel consumption, in a car I owned from 1983 to 1995 I did one of the trips mentioned above first at slightly above the speed limit and got 26 mpg then on the return trip I took it easy doing 55-60 mph most of the way and got 36 to the gallon. That's a 38% improvement.
In Milton Keynes, UK, where I live and do much of my driving, the place is renowned for its roundabouts (over 300 at my last count). To optimise fuel economy I ease off as I approach a roundabout and watch the traffic on or coming onto the rooundabout so that as I reach it, my speed matches that of those already on the roundabout and I have a smooth drive without needing to use the brakes or hard acceleration. I repeatedly encounter other drivers who overtake me, brake hard as they reach the roundabout, often having to stop to give way to traffic on the roundabout. I sail past them and am halfway to the next roundabout before they pass me again and the same behaviour is repeated roundabout after roundabout. They are either stupid ar unobservant as I make exactly the same rate of progress as they do. Today I was overtaken by a Porsche a mere 100 yards from a stationary queue - a complete failure to 'read' the road and traffic conditions ahead by the Porsche driver.
Yes, technology is a great help but good mpg is also in large part due to the driver.
* 1 UK gallon = 1.25 x 1 US gallon
