Turns out those old-fashioned ways of farming were actually pretty smart

[bhikkhu]

26. Or - think of it in a different way and it makes more sense

If you were given a few square feet of land, your choice of plants to grow, and unlimited time to care for them, do you think that (after a few trials) you could produce more food for that few feet than a modern farmer does in the same measure of land? Of course you could, and no great expertise would be required. If you have the time to optimize the plant mix, the watering and fertilizing, and make the most of every square inch with a succession of plants throughout a growing season, and give individual attention to your crops, of course you can outproduce, on a small scale, a professional farmer.

Look at "square foot gardening", for instance, which is currently a bit of a fad. It mixes varieties of plants in a way as to optimize the yield of a very small plot of land. It has a very high yield, and is very labor intensive.

Look at traditional practices, which have been very similar at various times and places. Farming, until recently in history, was the occupation of the majority of humans. Mostly it required a great deal of labor, and this was met in most cases by a high birthrate and large family sizes. On the death of the head of family, a common tradition was to divide the farm up between living males. Over time, of course, this often led to very small plots of land being intensely cultivated, in a way similar to "square foot gardening". The result was a very high yield per acre.

Look also at modern experiments on optimizing self-sufficiency, such as the "you can feed your family on 1/4 acre" thing. It can be done, there have been several studies, both practical and theoretical, and they all demonstrate higher yields per acre than modern mechanized agriculture. (or 1/10th of an acre - http://www.youtube.com/watch?feature=player_detailpage&v=NCmTJkZy0rM )

I don't mean to be overly argumentative, but I thought this was all common knowledge.

Again, modern agriculture optimizes profits, not yield.