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F=MA has not been repealed — those 2 second sprints to 60 still suck up a lot of energy.

Accelerating to 60 mph in 2 seconds does NOT "suck up" more energy than accelerating to 60 mph in 2 HOURS.

Actually, the most fuel-efficient method of accelerating is at a good strong throttle without blasting it. You want to get to speed (top gear) as quickly as possible, without pushing your vehicle into too-high rpms. There's lots of factors that go into it, but yes, while heavy acceleration does use up more energy, it then uses less energy to maintain that speed, while your slow acceleration is still under more load to accelerate. Also, most engines have a certain engine speed at which they're most efficient (generally 2-3M rpm), and very slow or extra fast acceleration will fall outside of that range.

Electric engines are a little different, as there is much less power loss in operation. Power to speed is a pretty linear relation, so the speed of acceleration doesn't matter nearly as much.

The reason many mileage comparisons say conservative drivers are better than heavy drivers is that they ignore the other factors that affect it more - top speed, braking, etc. The acceleration is a tiny part of the actual details - the biggest factor in mileage is how much you brake - every time you brake you're 100% losing all that momentum you spent so much fuel to acquire.

What you say is all correct...until your last statement “the biggest factor in mileage is how much you brake - every time you brake you’re 100% losing all that momentum you spent so much fuel to acquire.” While that is correct for internal combustion engines without energy storage, it isn’t true for EVs.

Tesla (and other EV makers) use regenerative braking where braking converts a lot of the kinetic energy to potential energy stored in the battery. That is the huge advantage of EVs, especially city buses, where it is constant start/stop all day long. It’s not much of an advantage for EVs outside towns and cities where you go long distances without braking.

Actually, the most fuel-efficient method of accelerating is at a good strong throttle without blasting it.

My original statement was based solely on Physics - without any consideration of possible differences between various types of engines, etc.

From the point of view of Physics, the amount of energy needed to accelerate a mass (e.g., a metal slug floating through space) to a given velocity is independent of the amount of time needed to achieve that final velocity.

Regards,