Yes, but even a model trained on a bunch of scientific papers will lack understanding in the same fashion, until there's some new technological breakthrough.

Understanding is not necessary for uncovering statistical correlations.

Neither is AI.

The parent poster wants it to suggest new farming techniques, which is a little more involved than plotting a trend line.

AI is simply about finding correlations in large data sets. Computers don't understand anything, they just shuffle symbols. So training an LLM on agricultural research will likely uncover patterns that would not be obvious to people and these patterns could point to new techniques and processes for increasing yields like scheduled flooding (as explained in the article). LLMs don't understand code but they consistently can complete code fragments which end up being correct more often than not. A model for yield optimization doesn't have to understand farming to suggest techniques and processes for increasing yields just like LLMs do for code fragments.

LLMs can complete code fragments because they're just matching them up based on having seen these code fragments paired together in they're database.

Yeah, just like a car is a CTRL + V of parts available on the car parts market.