Just getting caught up on your thread, eatpasta. I've only done a handful of races myself, so I'm still pretty much a rank noob as well and each race is like a whole new experience. You're definitely right about fitness, the fitness level required is far beyond the capabilities of the average Joe off the street, I don't think people realize just how demanding off road racing is. All the races I've done are hare scrambles back here in the east, so the terrain looks a lot different, but I'm sure the feeling on the start line is the same and once you get into the thick of things your heart rate also pegs at 180+ and maintains at red-line for the duration, just like back here.
Good luck your next race, it's great you have someone with a lot of experience to help - that's invaluable.
BTW, here's my most recent race, it turned out to be a very difficult mudder, carnage everywhere, it felt like my heart was going to explode in several situations. There's some helmet cam footage in there, too.
We have a race coming up in our series this Sunday, I'm not 100% sure I'll be able to make it, but so far that is the plan. I will be looking forward to seeing your next installment. As a beginning racer myself, it's good to see others' take on their experiences, so keep the reports coming. Good luck, and good luck to the Mrs., too, hope she recovers fully.