Well, I think I figured it out. The problem was twofold. The first factor was the paper I was using. I switched to COT 320 and it make an immediately noticeable difference in the quality of my prints. This is a very nice paper. The second factor was my print frame. It was a cheap frame with clips that only apply pressure to the very edges. I rigged up a clamping system that uses bars of wood to apply pressure in the center. It worked so well that it broke the glass. So, I made a few prints using two sheets of 1/8 thick glass that I keep on hand for contact printing on AZO. I put a magazine under the paper for extra padding and used spring clamps to hold the whole thing in a sandwich. Voila -- sharp prints.
Now I need to get new glass for the print frame and try my experiment again. The next step, I suppose, will be a new print frame when money allows.