I guess it's time to post again...
Executive summary: Sick since January 2011. Nothing definitive other than a bone cyst, seriously infected, excised in September. Was waiting for things to "just" clear, but they didn't—improved after the surgery to some level that's still too sick to run. But, was able to do elliptical without most if any symptoms. Running, bad; walking, bad, just takes longer to go bad.
The most recent investigative direction is
EIB. So far, so good (will hopefully post more).
Since I had figured out that the prescribed 15 minutes from inhalation to the start ween't enough, I did the two puffs about 80 minutes before heading out. Stayed at the 100-mile pace. Had almost no symptoms—just a little bit of chest discomfort. No dizziness/disorientation and no afterglow. Most importantly, no crazy high HR.