About 45 years ago I worked at an HIFI electronics repair shop (remember when folks got stuff fixed?). We got hold of 3M "Imperial lapping film" and developed a way to re-lap tape recorder heads if they were not too worn.
The heads would get grooves worn, and if the tape travel was not perfect, they would have dropout of highs when the tape rode up on the side of the groove. We used the film, in a series of steps, to grind down the head to smooth condition by hand, with the least possible removal of material at the gap. Since new heads were a couple hundred bucks, and we (mostly "I") could resurface a head and align the machine in under an hour and a half, we did a fair number pf them (no guarantee, but you save money if it works out).
The finest ones gave a good finish, and we had an 80% or better success rate. Just an odd use, but that lapping film really worked very well.
I have no idea just what it would be good for in scraping. That method you describe sounds rather uncontrolled, hard to understand how it is really a reasonable approach. "Accelerated wear", more likely.
Makes me think of the hobby groups with folks happily pouring 400 grit and oil on the ways and "lapping the machine back to accuracy".