Even on open roads with no one behind you the gas saved is not worth the annoyance of driving like this.

I agree. I'd rather walk or take a bus.

What I originally thought of as "pulse and glide" is working quite well for me and I'm still able to get the milage benefits you described. On 40 to 50 mph roads I have seen 57 mpg by gliding (battery assisted) for miles. I do this without a significant loss of speed thus it is not a danger or hampering other traffic.

If I'm on the interstate doing this and driving between say 70 and 65, it is not a problem either because in the right lane no one follows you reguardless of 70 or 65 driving and no one notices you loosing 5 miles per hour at that speed since they are not stuck on your tail.