| coasting is downright dangerous and means you are not in full control of the car, potentially causing a careless or dangerous driving offence.
when travelling downhill you should select a lower gear not higher and use engine breaking to control the car with assisstance from brakes. If you use a higher gear and control the speed using brakes you run the risk that on longer steeper hills you could overheat the brakes and ultimately be left with no means of stoping the car | 
