I am very interested in this type of coop. Unfortunately I would not be able to build it in the space that I have. I would not be able to make it as deep as it needs to be to function correctly. But I think it is a great design and more people should consider it.
In the book are plans for a 6' x 10' "backyard" version, which even back then (100 years ago) was intended for urban back lots.
BTW, for anyone wanting to build a house of this type, there is a book available for purchase on Amazon and other places. Modern publisher is Robert P, who has begun posting on this forum. Thanks to Robert, JackE and the OP in this thread for info on these type of open air houses.
All of those have inspired me to start construction on an 8' x 12' version that I hope to have done far enough to populate with chicks in the next week or so.