if you oil the seat it will get darker a bit at a time to a certain extent. If you want it allot darker then get some leather dye and add just a little bit of it at a time to your oil and oil the seat again, you can control how dark it gets from that point, the only downside to this is depending on how much darker you want to go (other then black) you may end up with a little bit of that patina (spelling?) look to it, you know that sort of weathered marble streaky look, which for some including me is a cool look, but to each their own. Start with a really good oil first and see what you get and go from there. Just like a new tan baseball glove after a season, it looks nowhere near as light as the day ya took it home, its skin afterall and will get darker with age.
not sure iof that helps at all.
