A lightly oiled file cuts fine. Try it. It doesn't clog up any more than a dry file either. The m1 oil dries to a very thin coating.We were taught to keep oil well away from the files as they then skid and clog up, especially on brass. They are always sold completely dry with no oil on them for this reason.
I watched a video from the 50's on file work yesterday and they mentioned oil or chalk to avoid clogging. I'm starting to think the dry file thing is a myth. I mentioned the dry file thing on Facebook manual machinist and half of those guys run oiled files.
Oil is necessary coming out of the vinegar and water rinsing. I see zero reason to over complicate things to avoid oil to stop the reaction. I blow 99% of it off after it's been soaked.
Eta: the video mentioned light mineral oil. Kerosene, or chalk.