I had the chance to tell the tale to someone two days ago. TLDR: I rolled the dice and it was literally like being in the Peace Corps. The problem came when I returned to The World, and it was no longer the same any more. My haircut didn't match my combat boots.
If I can find a new banana seat for the $80 single-speed coaster-braked bike I'll have to post a picture. Here's the original:
The derailleur failed.