Band on the left, lid on the right.
Well ... I thought I knew what it meant ...
I rarely have trouble with my water bath seals (in fact, I can't remember any of my water bath canned jars not sealing. Ever)--they're a bit more forgiving, but I've had inconsistent results with the pressure canner. And who knows if my bands are too tight or too loose? Not me!
So I did a little research and learned ... no one else seems to know, either. Or, rather, everyone knows, and everyone thinks it means something a little different.
The most useful answer I found was from Carolina Canning:
A practical way to determine if the lid is fingertip tight is to place the band on the jar, turn it just until you feel resistance, then turn the band one-quarter turn more.
So, I guess that's what I'll do.