When you're driving, and the traffic light up ahead has just turned yellow, then red, do you still step on the gas and speed towards it? Then at the last minute, do you step hard on your brakes, causing your car to lean forward and then lurch back sharply when coming to a stop?
Why do you do that? I guess if you're trying to get into the left turn lane in time for the next arrow, I understand it then, but otherwise, it makes no sense to me. If you're trying to beat me to the red light, then, well, congratulations, I guess. You win.
I'm no car expert, but it seems that doing this would cause you to use more gas and wear out your brakes faster. You're also really counting on your brakes to work perfectly. Luckily that usually happens. But as someone who was once sitting at a red light, and watched in their rear view mirror as a fast approaching car coming from behind DIDN'T manage to stop in time... well, maybe that's why I'm a bit sensitive to it. It's just one of my driver pet peeves.
So I guess my advice is, if the light ahead has just turned red, slow down! You have nowhere to go, and you can save a little gas with a little coasting.