This is a very interesting post. I had my project at a shop that used someone, I believe in MI, to do polishing. This person is an engineer who had developed a technique to polish glass that didn't leave dips or waves. He charged by the hour, $50 IIRC. When my car was in the shop, there was a B body there that the guy in MI had did the glass on. Everything but the windshield, which was too bad to restore, ended up costing $3000 to polish! But the polished glass on that car really looked outstanding. There was another B body at the shop at the time with repro glass and the glass looked crappy in comparison.
Despite the cost, I decided I really wanted my original glass polished. But everything with that ending up being (yet another) fiasco with my project. When he checked with the guy, he was really backed up, and with the other work on my project wrapping up, my restorer didn't want my car sitting around in his shop for 6+ months waiting for the polished glass to be returned. He found someone else who polishes glass and sounded promising in CA he wanted to try, so sent out my 1/4 glass to try them out and see how good they are. That guy then wouldn't return calls, so my restorer finally gave up after trying for several months to get a return call, told me to consider my 1/4 glass disappeared, and we ended up putting repro glass in my car.
The repro glass really doesn't look good at all and I am not happy with it, has a polarized look in certain lights, little scallops along the 1/4 glass edges, etc.
Then, 6 months later my 1/4 glass was returned "refused by sender". I wish I still had that CA shops name so I could list it as a place to avoid!
Like I said before, the whole glass issue with my car was a real fiasco!
My side glass is safe and sound stored at my house now, and I may want to try out your technique this winter to restore it, so I don't have to look at that mediocre restoration glass any longer.