Originally Posted by
daflorc
Bill: assuming they're aren't any irregularities in the blade, if you have a lumpy stone, the high points in the stone will take off more material faster and neglect the lower areas, leaving you with a razor with an uneven bevel.
You'll be able to hear it in a pass...it'll be a smooth, grinding sound....then in one part of the stone it'll show more resistance and you'll hear a louder, nastier noise... uneven pressure between heel and toe will give uneven bevel wear as well.