A friend recommended that I take an oily cloth (with regular motor oil or such) and wipe down the entire surface of my mountain bike frame. He claims that it's easier to hose off after, and it actually keeps cleaner. It seems counter-intuitive to me, as I think the dirt would just stick to the oil.
What do you think? Do you do this, and does it work for you?
I should add that this is for a wet, muddy climate; the argument being that oil repels water...