if you have a pole on a lighter background (an example), make a new layer for the pole and use the blend option "darken". it gives the darker pixel the spot. this will save you lots of time. and use masking if you dont already, its better then erasing.
oh yeah, and use lighten for a subject on a blown out background (Skier on snow, just check if they r wearing white T, might have a slight problem there)