It could be a study into the minds of legitimately insane geniuses.
Biodynamics is a beautiful concept, and a very important one to utilise. At it's core, it's about building health to the point where a vineyard's ecosystem can look after itself. The idea being that a healthy vine will defend itself against pests and diseases, as opposed to needing chemical treatments that will damage beneficial organisms as well.
I suppose just as importantly, it creates a necessity to plan ahead. It doesn't work as a knee-jerk reaction, it's mostly preventative. It absolutely requires an obscene knowledge of your vineyard and everything in it.
That's the part that makes sense at first view.
Beyond that, we have the rhythms of the moon and planets.
This part, I think is equally obvious and hard to dispute. The moon effects the tides, we see this clear as day; and just based on the water in vines and soil, it's pretty hard not to see that it can have an impact on how a vineyard will respond to any action you take. It has a very real influence. The planets... well, they probably effect it, I can mentally jump that far, but it seems a tenuous.
Where I get lost, is with biodynamic preparations. Stuffing cow horns with manure and burying them in certain locations at certain times, digging them up and diluting them in water to one part per several million and then spraying one drop per square meter.
Its flimsy logic at best, and it doesn't help that every book or article you read on biodynamic preparations will reference Rudolf Steiner (who himself, was very questionable) a dozen times in every paragraph.
For my day job, I'm a sommelier. That means a lot of study. You'll read up on producer after producer for hours on end, and the benefit is that you start to see patterns. The good producers are doing the same things.
One of which is biodynamics. It pops up with such frequency that it's very clearly worth looking into. Not only that, but the timeframe on a producer being good or bad almost invariably correlates with a shift to biodynamics (if they ever make such a shift. Many make great wine without it).
Honestly, I don't think it's causation. I think it's just that a shift to biodynamics means people care about quality rather quantity, and I think anyone willing to take on the extra mental burden of paying such close attention to their vineyard is probably going to be very good for that vineyard.
It's pretty controversial to speak out against biodynamics in the current climate of the wine industry; it's the niche that's becoming the norm (and that's certainly not a bad thing). I just think that sustainability, and encouraging the health of a vineyard is the priority. That's it. The best way to do that is debatable, but pay attention and listen to it, and you'll figure it out.
I just suspect that biodynamic preparations, and homeopathy are the wrong ways of going about it; but I respect it if it's someone else's journey to producing a better wine.