When I use the gearbox to slow down I take my foot off the accelorater and let the engine slow me, I also change down earlier and let the clutch out slowly and again the engine will slow me down. This is the way I was tought to drive so so many years ago, but my son who has just passed his test informs me that I am not driving properly and should be using my brakes more to slow down, he changed his mind yesterday when he was cought in the snow.