One of the things I think about a lot is productivity comparisons between conventional and unconventional agriculture. Mostly because that's the first question you get asked when you talk about anything that's outside the norm*, but, on what metric are we measuring? Per acre? Per hour worked? Per cost of input? Are we measuring yields of product or dollars earned?
This question also, to me, rings of fear. Fear of food shortages, which are really a problem of greed & distribution, not the world's capacity to grow food. If we were really worried about calories though, I think we'd at least switch to pastured animals instead of sending so much corn and soy to livestock (for any non-farmers out there, you do not get nearly the calories out of a chicken or pig that you put in- you get much less**). Or we would put more effort into making cities great places to live so we stopped turning farmland into suburbia. Or we would be much more concerned with how to prevent erosion & loss of arable land. But we don't, and we're not.
I also think of the complexity of non- conventional farming, and how instead of it being a return to the past, it actually relies on new information and methods***.
Take the plot of land that I'm working to make into a market garden. It's soil is, from a farmer's perspective, crap. It's gravely, sandy, very little organic matter. If I were to farm it conventionally, I'd basically have till to open the soil and kill weeds, and then provide all of the plant nutrients through fertilizers, which would cause the plants to kick out their symbiotic fungi, leaving them vulnerable to pathogenic fungi, and more dependant on me for water. There would also be bare soil everywhere, increasing evaporation & providing plenty of opportunities for new weeds. My costs would be very high, paying for fertilizers, pesticides, & herbicides, and I would have to water, a lot. It probably wouldn't be at all economically feasible to grow food on this plot using conventional methods.
Now, I look at it and say, I'm going to do no-till. I look at the hard, weedy, depleted soil and there's no way a seed is going to be able to come up through that. But, I'm not just doing no-till, because I'm not looking at it from a conventional mindset and just trading out one practice. I'm doing basically everything different from above.
Instead of tilling, I'm laying down a thick layer of mulch, to shade out the weeds, increase soil organic matter (increasing the amount of water and nutrients the soil can absorb & good on to), and feed the soil ecosystem. By the time spring rolls around, the soil underneath will be much better, but I'll still add more compost in most cases.
Instead of fertilizers I've had to pay for, I'm using mulches that I got for free from my gardening work & composts made for free from restaurant kitchen wastes****. I'm going to use over crops, plants that fix nitrogen and also serve as perennial hosts to beneficial soil fungi, which will also form symbiosis with most of my crops, increasing their resistance to pathogenic fungi while also providing them with increased access to water and soil minerals.
Instead of bare soil, there will be mulches and cover crops every where. Instead of monocrops & pesticides, I'll be intercropping which will help by hosting beneficial native insects that will chow down on aphids and other crop pests.
From this framework, there's an upfront investment of effort and planning, but farming this land now seems feasible.
And the thing is, each of those choices is backed up by research. We know so much more now about soil and nutrient cycling and how it actually works than when conventional ag really got started. We know so much more, and so many practices are new, so growing non-conventionally isn't a step back into the past of how things were grown.
But at the same time, it's not exactly completely information either- other cultures have different ways of growing food crops, and if you broaden your concept of what cultivating plants looks like, there's examples everywhere. We're just studying it now and providing it scientifically.
*and I honestly think that it's a result of the extractive mindframe that comes from being the decendants of colonizers. Just look at the different perspectives between many western foragers ideas and Indigenous peoples' relationship with the land.
** chickens are one of the most efficient, with a feed conversion ratio of 1.6, which means for every 1.6 pounds of food you give them, you can expect the chicken to gain 1 pound (cows are over 4 pounds of feed to pound of live weight, and pigs are 3 to 4ish). That's the whole bird though, counting all the parts we don't eat- guts, feathers, bones, etc. Even so, a pound of chicken food has over 1300 calories, and is about 20% protein for starter/grower, where as a pound of chicken has about 500 calories and about 30% protein (for dark meat, you get fewer calories from white meat). I'm not saying everyone should give up meat, but I am saying that the amount of meat in mainstream diets has increased dramatically, much of it comes from cafos where animals are fed on grains & legumes, and if we're measuring productivity and yield per acre because we're worried about feeding the world, this is a huge factor. Look up how much of the corn & soy crop goes to actually directly feeding people.
*** from a western, colonizing prospective
**** is this a particular boon from my particular circumstances? Yes. But everyone has their own challenges and resources, there is no cookie-cutter solution to all agriculture, everywhere. You have to find the solutions that work for you.