[andrewflnr]

And here I thought I was an idiot for wondering if just having people sleep in a position to help fluid drain from their lungs would help. I guess I wasn't so far off.

More prosaically, I think I've reduced durations of basic colds by deliberately coughing early on. Needs more experiments, but as you said side effects are minimal, so you may as well try. I'm starting to think this is a family of life hacks that should be much more widely known.