Felix discussed the polymer thing with me at length because the concept fascinated me and I kept bugging him about it. What he had conceived was a blend of engineered molecules which would produce a soft but stable substance like a soft Nylon, about the consistency of "bullet lube".
I took that concept as far as I could and consistently met with the same failure point that had concerned me in the beginning: Plastic grease melts and then re-congeals, making a nasty plastic coating in the bore akin to wad fouling in a shotgun, but lots worse. My conclusion was that burn-proof flouropolymers would be needed for such a grease to work, and they are so toxic and expensive as to be completely prohibitive. Metal soap/wax blend/paraffin oil lubes bumped with a small amount of ester or castor oil still get it done at my house for traditional lubing.
Polyester powder paint works extremely well. I've mentioned it many times, but it bears mentioning again that if it weren't for the distinct benefit of eliminating lead fouling in my suppressors, I likely wouldn't have taken a serious look at powder coating my cast bullets. But I did try it, it worked, and powdered paint "changed the game" as they say. I continue to explore the limits of what powder coating can do for bullets in HV rifle applications, how it can allow much softer bullets to be pushed fast with accuracy than traditional lubes, and how it can eliminate the factor of "bore seasoning" that is our nemesis when it comes to cleaning, and also eliminate temperature-related flyers.