Yeah, that was a good one. I think that Stephenson grossly underestimated the number of people who would have been Diggers - there are a lot of caverns in this world, and with two years to work on them they’d support a lot of life. And, after all, they wouldn’t have had to dig for geothermal power, it would have been on the surface for them, more than they could possibly have used, which was the problem, after all, wasn’t it? But great story. I love Stephenson’s work.
I thought the same thing, that there are so many caves and old mines that there would have been battles at the surface while people were trying to go down in them and stock them and set them up.
I had other problems with his vision of how it would go, but one of the main ones I was a little skeptical of was the idea that people would develop into fish men. I don’t think there is enough time to evolve as much as it would take.
The political maneuverings up in space seemed a little off to me, too.
But overall, the book was very thought-provoking, and the science was real. I learned a lot. A very enjoyable read.