I think I'd have to disagree with you on freewheeling - correct don't use the brakes, because you have wasted the energy getting there, just use natural engine braking. Also when freewheeling the engine will use fuel to turn the engine over and keep firing, however, keep it in gear going downhill, just take you foot off the accelerator - the momentum keeps the engine turning ie use gravity to power the engine not petrol
I am no mechanic/engineer - so feel free to shoot me down