Be able to communicate with Mother Nature's creature. It's a really helpful skill when you need to send a messenger back to the Park Ranger regarding your need for assistance with a crash related broken bone. Just kidding...

I'm very humble, but one of the biggest things that blew my mind on my frist trail was how long it took in terms of miles covered, vs road. I know that sounds rather simpleton. I looked at the trail map and thought, "hmm, ok... 6.5mi, how bad can that be?". Then I got out in the woods, well...

I think on what you need to do, you'll figrue when you come to the obstacle. Or re-riding the living he$$ out of the same obstacle until you get it.

One thing about mtb is that it is so nice to not have to worry about cars. That's fun in itself.