The binding goes twice as fast with two people, but not the printing.
Plus, I get the idea that the Webbs did not have a TON of type so they would set a page or two, print them, break them down and set the next pages.
If they had a linecaster then Jon could have set the whole book in a couple days and then they could have printed them taking turns. Very few people can feed paper for three hours straight, let alone for weeks on end. I have done it a few times, but it is VERY tough. Feeding paper is a small motion, but after a while, it starts to hurt. Walking up a flight of stairs is not tough, but doing a Stairmaster for three hours would be very tough.
My understanding was that Lou sold art during the day and jon set type. Then they printed it later that night.
Still, 3100 sets x 50 sheets of paper is 16,000 sheets. That is a lot of paper just to store.
I just finished 150 hardback books. Doing 150 books, there is no small step that does not take a LOT of time. Even something simple like gluing the edge of the text block for the book. For the Webbs, it may take them 2 minutes per book, but for 3,100 books, that comes out to 103 hours, which is almost 13 eight hour days.
...and that is only one step out of dozens of steps. I cannot express how much work it would be to do 3,100 handmade books. Even with all of the conveniences that are out there, it would be a monumental task that would consume your life for a long time.
Bill