Hi Martin,
There is a product called OptiClean that I would recommend using before any polishing with a cloth. It is a fluid polymer, packaged in a bottle similar to those used for nail varnish, and you apply the stuff to the lens surface with the brush. It dries quite quickly then you remove it with a piece of tape. The whole layer comes off as a single sheet, which looks very much like a circular piece of clingfilm.
OptiClean will remove some greasy marks but more importantly it will pick up any specs of grit or grime, including some which won't shift with a blast from the aerosol. I've made this a part of my cleaning procedure ever since I put a nice scratch in the rear element of my 35/1.4 Distagon, just shortly after acquiring it.
Also, regarding canned air, I've switched over to the small CO2 canisters, since with the regular aerosol cans I find you have the choice of either holding them too far away to be fully effective, or else holding them close enough and getting propellant on the glass.
Wilson, have you tried one of the Ilford anti-static cloths? Sounds like just what you need.
Regards to all,
-= mike =-