I haven't had any luck with heating the vulcanite to remove a tooth indention, tried that on the double-comfort CP stem.
Depends on what grade steel wool (fine, super fine, etc.) .
One guy who showed me some metal polishing tips uses oil instead of water for wet sanding aluminum. He says water gets into the aluminum. I wonder if using something like mineral oil would work on a vulcanite stem? To this point, I've been using a mild oxy-clean/water solution.