Good luck to the author. Having a tractor around just to move things (mulch, etc.) is very useful.
You can generate a significant amount of output in a relatively small space. Two years ago (last year was weird) we netted ~7 gallons of blueberries, 60+ lbs of tomatoes, 25-ish lbs of okra, 20+ lbs of bell pepper, 45+ lbs squash and 10-ish lbs of corn (a storm destroyed 2/3 of it before any popped up). We did all of this on approximately 1/5 of an acre, with plenty of room between rows. It was all for personal consumption - froze and canned everything. We plan to do more this year with some expansion. However we do till, but make heavy use of mulch for weed control. Pest control is handled with neem oil and biological controls (marigolds and yarrow).