Re: buffing during relaquer
If the proper liquid method of lacquer removal is used, there should be no metal loss. And you would add the minor weight of the lacquer back in when re-applied. Remember, horns are occasionally chemically stripped and re-lacquered at the factory before initial retail shipment. Lacquer is there to protect the brass and performs a good function.
The thing is, some very protected areas may receive double lacquer and of course engraving will be filled to some extent. Later.