How to make Bluetooth tethering work?
As noted, the other question linked in the question above is very similar, but for older versions of Android.  I did finally manage to connect my phone and tablet after finding android weasel's answer to this question.  Apparently, the prompts and status messages are poorly designed, but once I understood what I was supposed to see, I got the connection working.  Now, I can tether my tablet to my phone in under a minute, and use the larger screen and keyboard online anywhere I have cell service.