So I went looking for answers, or at least insights. I read about 3D gait analysis one night randomly (probably on someone else's blog) and when I found out that there was a facility less than three hours away, I had to look into it. And it turns out that my most recent PT knows the director of the lab and he was able to brief him on my case a bit in advance of my arrival.
Max, the 3D guy, also set me up with an appointment with UVA's head physical therapist, Eric Magrum, who is pretty well known as a runner-fixer. The only thing I couldn't make happen was an adjacent appointment with the medical director of the program, who literally wrote the book on running. But I still got a lot of info.
Here is the raw data I got. When you see that I was "running" at 5.3 mph, you will get a good sense of how much I've been struggling lately. I wrote a lot more here previously about the conclusions and recommendations I got, but then I forgot to save it. I'll let you all stew on this and then will report back in Part Two of this saga.