everything i know about wet sanding is you have to soak the sand paper in water for atleast 24 hours and then sand with it, making sure that the surface is constantly re-wet basically you want the surface really wet and the sand paper really soaked so that you dont scratch anything too bad. then you have to polish the surface with some kind of polishing compound so that you get all the tiny scratches out and it shines nicely.
i think using the polishing compund or a mild scratch removing compound then a polishing compound with a random orbital buffer should be just fine, you dont want to remove too much material, just the surface oxidation as stated before
I just talked to my glass repair man... Use 3m Finese-It and a buffer on medium/low speed.. He has a "special" compound that he uses that costs $90 lb but the Finesse will do. He says it usually caused my automated car wash soaps/polishes.. Make sure if you use a buffer to do the low speed thing. You don't want to overheat & melt the plastic lenses..