But then you introduce the new 850 with the flip-out mic that turns the
unit on and off...  Kind of like no one bothered to test the 820 outside of
the lab, or maybe they wear it on the ear at all times, and never put it in
a pocket, or are most concerned with being small, and not functional, or
...

On the other hand, I did run my HS820 through the washing machine in a
pants pocket.  I had put it into a cargo pocket to avoid the button press,
and then I forgot to empty that pocket.  I let it sit for a couple of days,
recharged, and it seems to be unaffected.