I went to visit Bill Sweetland in the early 90's, and had a great technical conversation with him about his process. I had been experimenting with stabilizing wood treatments and compression. We discussed his process in detail, and when I expressed interest in resurrecting the process with my methods, he recommended against it. Apparently he never made money with it (or enough to justify the hassle), due to its complexity and the expense of production. After I researched it enough, I believed him and didn't pursue it commercially, although we made some nice stuff in our experiments, shafts that were stabilized and compressed by about 50%. I still have a few of them around here somewhere...
A really nice guy, and a very enjoyable visit.