Sustainable Compost Production

I'm fascinated by the idea of sustainability. John Jeavons says growing lots of the best carbon (grains)  & nitrogen (legumes) crops are the key to sustainable plant based compost production. He recommends 60% of your annual garden space be devoted to growing foods that produce the best compost materials. Has anyone tried this and if so, what were the results? Are there other strategies for sustainable compost production? From what I understand, small livestock like chix, rabbits, ducks, etc have to be supplemented with feed from outside sources.

I can't speak to exact percentages -- I imagine the amount of biomass you can produce would vary based on climate, rainfall, length of growing season etc.

I do know that feeding your growing area requires biomass many more times than your garden will produce. I have never tried to make a closed circle, but in my current sandy locale and climate I think it would take at least 5 units of biomass area to feed 1 unit of food production area.

I feel that using your precious  garden space to grow compost is a waste of time and space, a cover crop that you either till in or just cut down fine but specifically growing plants just to cut them chop them up and compost? Legumes don't produce nitrogen in their leaves any more than other plants and nitrogen in the soil is minimal unless you cut the plant at the right time and instantly replant with your preferred crop.
For me in my climate a 2000m2 garden (half acre) provides enough scraps in the form of leaves, weeds etc to make enough compost for about 150m2 that's including all of our kitchen scraps and some lawn clippings as well. to grow all my own compost I would need to use about 2 acres assuming I used higher biomas plants like maize.  
So I would estimate that I would need 1:8 to grow enough compost.

https://en.wikipedia.org/wiki/Old_Rotation


"The Old Rotation is a soil fertility experiment on the Auburn University campus in Auburn, Alabama. The Old Rotation experiment, which started in 1896, is the third-oldest ongoing field crop experiment in the United States and the oldest continuous cotton experiment in the world. It was the first experiment to show that a cotton/legume crop rotation would allow soil to support a cotton crop indefinitely. The Old Rotation is listed on the National Register of Historic Places."


The experiment continues on........

Explanation of experiment.




Time Lapse

Experiment
The Old Rotation consists of 13 plots of six planting systems:

A control test where cotton is planted without rotation or fertilizer
Cotton rotated with winter legumes but not fertilized
Cotton just fertilized
Cotton rotated with corn and winter legumes
Cotton rotated with corn, winter legumes, and fertilizer
Cotton rotated with corn, winter legumes, and soybeans[3]
After 110 years of continuous plantings, cotton yields remain high for the rotated plots, producing nearly three times the yield of the unrotated plots.