For years now I have been letting tree leaves fall on the ground in the fall and stay wherever they fall. The result has been extremely fertile soil that seems to make it easy to grow most anything. It basically forms a natural compost. I'm convinced that gardeners who bag up their leaves and send them away or even compost them are missing out on natures own way to replenish the soil. (I do compost the weeds that I pull though).

It seems like what I'm doing is basically similar to what you are doing because I too end up working the leaves and stems into the ground when I get the garden ready for planting. But it might be more of a benefit for next years plants rather than this year's because it takes time for the leaves (or your corn) to break down and release those nutrients.

Unfortunately, old corn stalks have very few nutrients to add to garden soil. Even in compost, they will need some nitrogen-rich materials to help them break down. When you put corn stalks or fresh leaves or sawdust into the soil, they suck much of the nitrogen out of the soil to use in their own decomposition process. This is counterproductive to building soil fertility.

I would collect all the corn stalks, make a flat layer of them over some good soil outside your garden beds, and then start a compost pile over them. They will assist in air entering the pile from below, which will speed up composting. After six or eight months, aided by the nutrients above them in the pile, they can be added to soil if they look like they have rotted adequately. The website below has a lot of information on composting. Click on "Techniques" then on "compost."

Here is a link that might be useful: Alan Chadwick

Nutrients aren't everything. The stalks will produce humid acids and feed the earthworms, who will turn the soil over the years. I think grinding vegetable residual in place is the way to go, and I do it all the time. There is no possibility of increasing the nutrients in the soil by taking it away and composting it elsewhere. Caveat: if the vegetable is diseased, I prefer to bury it.