[dcb]

Another thing to consider is that p&g effectively reduces engine and much drivetrain friction. If you pulse for 1/3 of the time then your engine (and valves and alternator and???) and most of your transmission gears are not turning for 2/3 of the time you are driving.

And of course if you glide up to stops and wait with the engine off, then less to zero fuel spent idling.