200 FF Storm Grey
If you coast in gear then you're obviously going to slow faster than if you coast in Neutral. The trick is working out which one is more fuel efficient for your car / road conditions.
Eg Coasting down a 40 mile hill in gear will save more fuel than coasting down it in Neutral.
But how many 40 mile hills do you know .
I don't think it does mate, I aint the most mechanically minded of guys but iirc when the car is out of gear it uses more fuel just in order to keep it ticking over where as the gears them selves would usually keep the engine turning over without a need for fuel (when you're slowing down) so say you're coming upto traffic lights, if you leave it in gear and let it slow down by itself you're using no petrol (or as good as)