Originally Posted by gkirk
This is incorrect, the rate you speed them up makes no difference. The amount of energy in them is a function of their rotational inertia and how fast they are spinning. How fast you get them to that rotation rate makes no difference.
Besides, the energy is lost when you hit the brakes.
Are you saying that a full throttle blast up to highway speed will produce no difference in fuel economy compared to gradually and gently getting to highway speed?