Jason,
Great question. I am exploring this myself.
I would not use our DE/CB product or any other DE product as a large scale soil additive. But from what I remember off the top of my head, DE has roughly 20 trace minerals - CB has roughly 80 trace minerals.
I am interested in testing DE in zone 1 type applications for very controlled areas like a specific bed or containers. Also, I have about 300 blueberry plants in pots right now. I was amending the soil to put them in the ground, but after calculations, I might decide to put them in 25 gallon pots. I have experimented with making my own
coffee grounds soup for the blueberries. I like the results thus far. I was thinking about adding DE as both as a soil additive and as a fight against japanese beetles. I might run some test samples and just observe.
CB is very alkaline and maybe could adjust soil pH over time? I would not put CB in my blueberry soil.
The key for me is that rain erases all DE insect killing, but the problem there could be the solution of distribution of trace minerals as the DE gets sent all over the place. Maybe, maybe not?
Those are just my thoughts. Blessings.