Just a little past experience. I am no longer a farmer, I quit back in the early 90’s. When I farmed I was close to the area ST is from, southern MN. Back then we just started to experiment with cover crops. We would plant winter wheat or oats into our soybean fields, corn never came out early enough to get anything growing to matter before winter came, and in the spring once the ground thawed and dried out, we were back in it planting. We always rotated crops, so the fields that had soybeans in it, would have green manure in it the next spring to plant corn into.
The rotation went like this. Plant soybeans, combine soybeans, disc soybean field, plant oats/winter wheat in the fall, then in the spring spray, and just plant the corn into the green 3 inch high cover crop. Corn fields always got plowed under, even though chisel plowing was becoming the popular thing, we didn’t have the equipment to do it, and we new we were on our way out soon, so we didn’t want to change things up much.
Planting a cover crop into a corn field just wasn’t possible for us then, by the time we combined, the ground was pretty much frozen, and there would be no way to get the seed in in the spring time without burying your equipment, prior to needing to plant your cash crop.
Now my land is even further to the north, and less time for cover crops to make sense.
I guess my point in all of this is, what works for some people, won’t work for others, whether that be demographics, regional, soil conditions, (hard clay), or in our case spending a lot of money on new equipment, when money isn’t there. Hard to spend several thousand on new theories, when you are barely getting buy now, when the old way is working, and you are able to make a small profit.
To the original posters question, black dirt over winter isn’t the best thing for your soil, but in my area, if you don’t work up the soil in the fall, you may not get enough time to do so in the spring, to still have time to get your seed in
