MikeW
>Induction hardening of the teeth would make it a throw-away saw. Induction hardened teeth can snap when reset depending on how far past the bottom of the gullet the hardening occurs--Rob's saw can be reset when needed (after a few sharpenings) for the life of the saw. Which seeing how I have some saws nearly as old as the US...

The teeth will remain sharp for quite some time. With *very* little practice, anyone can learn to sharpen a saw adequately.

fwiw, I have used the same DT saw for sawing kerfs in the Bubinga handled saws LV carries for a year without resharpening. Way longer of a cut than DTs are typically cut in a board, twice or thrice as deeply. They do remain working sharp in hard woods for quite some time.

Take care, Mike
not Rob today nor any other day...