When I lived near Luton, being on top of a hill we often got snow, and I always cleared about 100m of pavement, including the bit around the corner shop. Once the sun came up, even the feeble rays would then melt away any remaining bits leaving it completely clear and free from ice. I always assumed it was because the black tarmac absorbs the small amount of energy from the sun and turned it into just enough heat to be useful.
None of the neighbours on the other side of the road bothered doing any clearing, meaning their pavement was lethal with all the icy ridges caused by people walking in the snow, whilst everyone on my side was very appreciative of not slipping.