I'm back from Portland where I had the folks at Advanced Arm Dynamics build me the socket for Will Craigs bike arm. The arm works great. I got in two rides while I was up there - one with Kerstin (the OT) around part of Lake Oswego and one solo ride along the river. They wanted to finish the arm (make the socket out of carbon fiber and paint it to match my bike), but I wanted more time in the saddle (and socket) before we made the jump from working model to final product.
Last week I went out on two rides and everything worked great.
My left hand did get sore so I might get stuck with sub-1hr rides, but at least I'm out again.
Here's a short video (1 take with no editing so dont expect much) of me putting on the arm.
To see the inventor using the arm check the 3/3/13 post - "Trailblazer"