'twas ever thus
45 years ago, as a manufacturers test driver, my Dad turned up at Silverstone for the testing for the MPG figures for a new car. He was able to increase the MPG by 15% with little tricks such as coasting on the straights, and changing gear when the engine really wanted to (rather than when people *thought* the engine wanted to).
We also worked with a major insurer on a warranty policy. They specifically wanted a list of all items he had never had to change in 40+ years of experience. He wasn't too surprised to later discover that these were the non-excluded items on the policy.