I have a white leather covered "Turbo" saddle on a Bianchi road bike that is very comfortable but showing some wear. It was looking pretty grungy so wiped it with some isopropyl alcohol. It didn't really clean it up much and if anything I think I dried the surface out a bit. I suppose applying some proofide couldn't hurt, could it?

alcohol dries things out. Not good. I'd put some sort of sneaker conditioner on it and then wipe it down thorough so you're not looking like you've got a case of the bird sh1ts when you get off your bike.