That 60s Super Blackhawk is more of a testament of "being taken care of, and not abused" than the tune that was put on it. In many ways, a revolver wears out, while an auto loader wears in, to a degree. Had that hammer been "yanked on repeatedly" over the years, it wouldn't have mattered how good a tune it had had. And there aren't many movin parts in a single action to begin with.
Many times car doors on new cars, have to be pushed shut because the "new body" is so tight. That tightness fades with use, just like a pump shotgun slide will. As far as the tooth paste trick? That's a new one on me. We used to use toothpaste and a brush, to bring the shine back up on our badges, and collar brass, but never heard of it used on guns. If a shotgun were brought to me, (and they brought many), that had a few "hangs" in it, I tore it down, and the "hangs" were easily identified by the tell-tale scratches in the bluing. A dremel tool and a little jewelers rouge, took care of this. However. The gun would have worn in on its own 99.9% of the time anyway.