I disagree, and so does this:
Click to see the chart like Daox's below.
Any time the engine would be idling more than 10 seconds, it's off. I drive with 2 modes: Pulse, and engine-off glide. No need to use fuel idling the engine when it's not doing any work, especially when sitting still!
There's probably a slight penalty with each restart, but Scangauge doesn't have the precise measurements to show if it's 2 seconds or 10 seconds worth of fuel. I just call it 10 and go from there.