While I definitely agree that sometimes we have to cheat, for financial or other reasons, it's not a good permanent fix. If you repair anything but the most superficial of scratches, you should get new glasses as soon as you get the chance. Any time you polish your lenses using these techniques, you're changing the shape of the lens, altering how it bends light on it's way to your eye. Depending on how drastic these changes are (it doesn't take much), they can be harmful. If you can't afford to replace the lenses, you might be better off with the scratches.
P.S. I don't think "Grimey" expects to profit from his advice to a distant stranger.
Dave
July 2009