Just having some fun with this one.
I've read about Johnson-Su systems and even met Johnson and Su at a conference a few years ago and was very impressed with the results they get in terms of crop output and the microbial diversity of their compost. The system is not for me, though, because I want to have access and continually add things to my compost, but I only dig into and process the top layer of my piles, about a foot deep. The pile is in a big wooden bin about waist high, so turning and forking and shoveling don't require bending and straining my back. But the bottom layer consists mostly of brush and wood waste that I put there when I started the system, and that material has been undisturbed for 5 years. So I assume there is plenty of fungal activity at that lower level. When I dig down that deep the compost is black and compacted like dense soil, with just an occasional fat worm at work, quite different from the lively top layers.