The Lean Micro Farm

I wouldn't mind reading one of his books but wouldn't pay £30 for the privilege. I've looked at his site and he doesn't really say what he does but is promoting his courses and books.

It looks like most of what he does is salad crops that he can get a reasonable return on, tomatoes is no.1 crop - which is what really market gardening is, not farming. I don't think you could feed many people off 1/3 of an acre (especially if they eat a lot of meat) and that isn't his aim. His aim is to make a living off as small an area as possible and sell his books and courses.
Quite a few youtube videos that confirm salads and a fast growing roots - carrots, turnips. A few here:

https://www.youtube.com/playlist?list=PL...Yug0wIMxty

I think you could probably feed one person off 400 to 500 sq. yds. or about 10 people per acre but there would be no meat or eggs, a pretty boring diet mainly beans and potatoes with onions, peas, salads, herbs and tomatoes. But beans and potatoes would not provide you with much money and I don't think cereal crops for bread would work on a small scale either.