Based on my experience with using laboratory diamond saws, grinders, and other laboratory equipment and relying on what I was told about the small diamond edged saws and grinders ability to cut rock, the method I outlined should work without a need to use the bonding agents which you described. The purpose in the sequence described is to quickly prepare thin sections especially when one does not have access to lab saws, vises, etc. If I follow your approach it would be like going back to mounting the specimen in a vise, cutting a chip (1/8") off, mounting on glass, cutting it again, and then hand grinding it down. UGH! I don't have such patience.
Perhaps I was not clear in my description. The objective is to get a fairly smooth surface, mount that surface to the slide, cut/grind a good really smooth surface (using rotary motor), mount final glass there, cut to remove old glass and grind to near final thickness so final hand grinding can begin. I made a jig to hold the slides for the process. Hope this is clearer, probably muddied it worse, so will apologize now.
Have fun with it.