Chunky, I asked a question, it's perfectly possible that they answer to that question is "yes, I've underestimated how challenging mountain biking is". Not really a surprise when I've been doing it over 20 years.
Having said that, my comment was posted after they'd crashed in the UK and the novices I've introduced to the sport seem to be more capable that what we saw (which was obviously edited to show what they wanted). However, for novices, I was impressed with the way they were riding off the concrete in the school near the finish.
I may not be the best, but I'm pretty flippin' good. Thanks for noticing 😉