If traffic is moving at less than 20 mph, but I still have to stop breifly every 50 yards, I'll slip it into S. It helps so that the engine doesn't rev when accelerating again, better than from full autostop. It keeps the coasting drive more steady, and I think it saves my efficency, too. But, I am still experiementing with it, and I do have to remember to put it back in Drive when I get to a point where I get to go faster than 25 mph!

Mostly, I avoid heavy traffic if possible. I check the sig-alter website before I leave work, and if the worst spots are red, I go over to my parent's place for dinner and wait until traffic is cleared before getting back on the road .
Or, if I can't do that, I use the car pool lane and get off at the next available exit to take surface streets home.

--A