VGA display no longer being recognized by Late 2016 MBP OS Sierra
It's a bug.  If I leave the USB-C adapter plugged in, the VGA can be connected and disconnected without issue.  That's the only way, other than my weird multi-adapter method.  Kinda sucks to have to leave the adapter in, but that is the only way.
  I actually got a whole new MBP just for this issue, and the new one acted exactly the same BEFORE I imported any files or settings.