No, they don't. So what do I think I "gained"?
I have a newfound sense of adventure. At the beginning of the event, when the other teams continued on along the sealed road, my first instinct was to wonder whether they were lost. They weren't; they'd just chosen a different option to us. Early on, when things were tough, I'd wondered why we hadn't also chosen "a different option" but in retrospect, I'm glad to have had the experience I did, as hard as it was.
I gained a couple of blisters. Big ones. But they'll heal.
I gained a fantastic memory, of an excellent experience with Miri. The last couple of times I've ridden with her I've felt humbled at what a patient and encouraging person she is, and how lucky I am to have her as a friend. She stuck by me and looked after me. Thanks Miri!
We gained a second placing. Mostly, when I enter a race where there's three entrants in my category, I place third. We did well.
I gained an appreciation of how much fitter I need to be in order to contribute effectively in a team situation.
I gained an idea of what I can achieve on the mountain bike. Before Sunday, the total time I'd spent offroad on my mountain bike wouldn't have been much more than four hours in total. To spend that much time in one go, and survive as well as I have (blisters aside) is something to be proud of, and build upon...
Ironically, for all that I gained through this experience, I also learned that there's still more to gain.