(Health and) Efficiency

I once had a boss. A PhD from Oxford. You might have guessed from meeting him.

He knew (I didn't ask, you just don't with people like this) that the engine of a car is most efficient at 75% of load.

So, his driving style was
a) get into fifth gear as soon as possible, even if it knocked
b) on a motorway thrash it to 95mph, drop the clutch, put it in underdrive (neutral) then let it slow to 50mph. Repeat. After 300 miles this gets to be REALLY tiresome.