W R O N G !\nFor an efficiency excercise, switch off the engine!\nAt my last job, the journey each way was give or take, ten miles each way. Each day i was able to coast with the engine off for a good four miles thanks to the terrain of dual carriageway with long hills.\nOn the way back i could accelerate up to 80mph and coast all the way down to the main roundabout which was just over a mile and a half and then if all was clear, take the roundabout at around fifty and then coast a further three quarters of a mile to the first set of traffic lights along the flat.\nMy mpg went up considerably driving this way :)