They mean it!
We rode 50 miles on bicylcles yesterday, 16 of which was on a primitive trail. That 16 miles took 9 hours, and was more like using our bikes as weed whackers, not even riding them. There was times where we had to use our feet to find the trail because the bushes were over our head, and we couldn't see down to see where the trail... had been. That 16 miles took 8+ hours, that is less than 2 miles an hour... Well, done that trail, don't need to ever again. Resurrection River trail just north of Seward, Alaska. The first 12 miles before we hit that trail took about 50 minutes. If I ever go back there it is because the forest service is paying me, and I have a weed whacker and a chainsaw.