Ah, the list of
in-your-face links that prove everything without any valid explanation.. What do you think these commercial links demonstrate? When so-called experts hope to sell me something, they are no longer experts, they are merchants. In addition, you seem to contradict yourself with this one:
https://acousticguitar.com/ask-the-expert-is-fingerboard-oil-snake-oil/ I quote a passage:
"Dryness is the only sure way I know to get a crack in your fingerboard. So, no, wood doesn’t need anything smeared on it to keep it from cracking. All it needs is a stable, properly humidified environment."
I'd like to know why
you think you have to do it. Because you were told to do it? Do you play piano? The black keys are ebony and are not oiled. Do you play chess? The black pieces are ebony and are not oiled. Do you play violin? The ebony fingerboard does not need to be oiled. Today we still have violins that are over 200 years old and whose fingerboards are in perfect condition. Again, you can do it, but you don't
need it.
I hope I did not offend you, I just wish to restore the truth.
to clean or not to clean...