Yeah, that's why I included "per unit of land." It is in practice a little more complex, and a lot of times the smaller farms are more labor-intensive.

My opinion is that modern farming is efficient enough that we can very obviously sustain the farmer, and sell the food at a reasonable price, and it all works -- the only reason this is even complicated at all and we have to talk about optimizing for labor (certainly in 1st-world farms) is that we're trying to support a bloodsucking managerial class that demands six-figure salaries for doing fuck-all, and subsistence wages for the farmers and less than that for farmworkers, and stockholder dividends, and people making fortunes from international trade; and if we just fixed all that bullshit then the issue would be land productivity and everything would be fine.

But yes, in terms of labor productivity it's a little more complex, and none of the above system I listed is likely to change anytime soon, so that's fair.