I am grateful to Nate, Swine Flu, and an anonymous poster on Slashdot, for pointing me at this:
http://www.phoenixchildrens.com/emily-center/child-health-topics/handouts/CPT-55b.pdf It's a fascinating technique. The jist of it is drumming on the lungs to shake loose any nasty clumps of mucus. One curiosity-experiment round of that and I got out a ton of stuff, including the persistent infection in my lower left lung, and regained an impressive amount of lung capacity. Best lung fixer I've ever come across. I heard from
wetdryvac that this is also used by some runners.
From a ninja perspective, this is a wonderful application for Happa Ken, which is a strike we hardly ever get to practice, since its primary damaging applications are things like bursting eardrums. I find the idea of striking as a medical technique fascinating, and am delighted to have an interesting way of practicing this strike.
It's possible for me, with my silly flexibility, to reach all the striking points so long as I use a different strike on the lower-rear one, but it's more difficult to relax into it when doing the technique on myself, and tensing up prevents the percussion. I'm looking forward to seeing what level of long-term improvement occasional use of this can produce for me, and curious whether it helps anyone else who feels like trying it.