Also, where has anyone heard stopping slowly increases mileage? Maybe in a car with regenerative breaking, but certainly not in a good ol' ICE powered car. If your foot's not on the gas, only idle gas is going to the engine (unless the computer is doing something, but it shouldn't affect that much). Unless I'm missing something, I can't see how slowing down gradually will increase anything beside the frustration of the driver behind you because you're not getting to a stop light quicker:-P
I think the idea behind increasing gas mileage by stoping slowly is based on the thought that if you stop slowly while approaching a light, you may not need to fully stop at all.
If you reach a stop light quickly and convert all of your kinetic energy into heat, you need to burn a bunch of fuel again to return to speed, but if you approach a red slowly and it changes to green in the meantime you don't have to expend as much fuel to return to speed.
This is what I find most surprising about the parent poster's report of no fuel savings. If he was doing a good job of anticipating reds he should have seen some savings.
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or are you just happy to see me?
I think the idea behind increasing gas mileage by stoping slowly is based on the thought that if you stop slowly while approaching a light, you may not need to fully stop at all.
If you reach a stop light quickly and convert all of your kinetic energy into heat, you need to burn a bunch of fuel again to return to speed, but if you approach a red slowly and it changes to green in the meantime you don't have to expend as much fuel to return to speed.
This is what I find most surprising about the parent poster's report of no fuel savings. If he was doing a good job of anticipating reds he should have seen some savings.