[KarlInOhio]

batteries have a finite number of charge/discharge cycles before they begin to fail. Bloomberg noted that concern near the end of their otherwise sunny report on this idea:

I don't even like the "Auto Idle Stop" on my car. If my car is stopped it can turn off the engine and then start it again when I lift my foot from the brake. I can turn that system off, but it always comes back on when I turn off the car. I don't want the extra wear and tear on my battery, starter and engine to save a few drops of gas, so I try to remember to hit the button every time I start the engine. There is at least one aftermarket solution which electrically duplicates the button press after you start the car.

[spokeshave]

Even better is a stick shift...pop it out of gear and coast to the stop sign in idle......My 1978 F100 ticks over at about 300 rpm.