The proof is in the production

A few years ago I started really pushing the boundaries of polyculture. Planting veggies, fruit, herbs and flowers way to close according to the seed pack recordations. Well it's been a progression. Each year I push it a little farther. This year a couple of my beds are to the max. Still the product is amazing.  I'm not saying it's for everyone.  I imagine if you live in a wet, or very humid place this method would be a mass of fungal disease. There have been failure along the way. Garlic didn't do well at all.   I also have to ruthlessly prune sometimes. But for the most part it absolutely amazes me how well everything does. Production is way better than when I planted in a conventional way. So far ( I hate to tempt fate and say out loud) little to no disease, or bug problems. We have already eaten lots of zucchini and squash, cherry tomatoes ( the birds? Or something beat me to the first two ripe regular tomatoes) carrots, kale, Swiss Chard, beans, egg plant and peppers, I started both from seed this winter, not only is there a lot, but they are quite early. Peas are done for us they weren't surrounded by other plants because I didn't get my fall/winter crop in last year, and so far it's one of my more crummy crops.
The beds with all the melons is a first year experiment. We will see what happens.  So far everything is growing very well. I predict in a few more weeks I won't be able to see the ground.
For me this method is a win. It looks messy, and you may have to dig for what you are looking for, but we are enjoying eating from the garden every day.

I always wonder about those recommendations and whether they're legit or not.  It sounds like, at least under some circumstances, they're not.