Some good points, Steve.
In cleaning up the fall garden, I dig a few small areas and bury some of the more done stuff from my compost piles. if I plant over that right away, like radishes, I add some fertilizer mixed in with the surface, as most of my stuff at that point is cold brown leaf remains.
In planting hills of squash, I try to always bury a good pile of previous years compost- often, mostly brown leaves.
So here, I'm not exactly in-ground composting- I am in-ground finishing the process from months of above ground.
My biggest limiter to in ground composting is space- where I want most soil improvement, I am also trying to grow crops as much of the year as possible.