I do what RAS does....nothing on stainless and a little light oil on carbon blades.

It seems I'm always washing a blade. Every time I use one, even if I've only been whittling and the blade gets a little sap or other tree-gunk on it, I wash it under HOT (hot as in hot) water with a little dishsoap on a sponge. Then it gets rinsed with HOT water and dried with a cotton cloth. Then it's done. If it's carbon I'll put a little oil on the blade only if I think I won;t be using it for awhile.

For folders, I oil the pivot when I remember to do it. I may wash a folder (HOT water) and not oil it after, but I will when I think it's been awhile since I did last.

I never heard of storing a folder any other way than just closed. That's new news to me.