The way I see it, you are just layering in different types of compost, with out tilling. This is a good way of getting coarser materials to rot down faster. I think the drawback is that you have certain materials at different levels, where that it be better if mixed in the soil so that all roots could have access to the same mix. Pepper plants will send out roots 4ft below the surface if there is "food" for them down there http://www.ces.uga.edu/pubcd/b1027-w.html Byron