has anyone used this gear drive?

A local racin legend around here, WL Kitchens showed me a trick years ago to make gear drives completely silent. He made a jig that held the gears and tensioned them together. Took some coarse valve grinding compound and slobbed it all over all of the teeth. Then he drove the gears with a hand held drill and lapped the gears together. That was with Chevy gears, but I am sure it could be done with others. He had an El Camino with a small block and a complete exhaust and you could not hear one iota of a gear drive in that joker, but it was sure there.