Per Adam's suggestion, renaming the variables did the trick. My table
was already structured with underscores in it, so I didn't have to
rebuild my schema or anything, I just needed to let the framework do
its naming magic and get out of the way.
Thank you for the tip about the class keyword. I had tried the syntax
with and without the class keyword and, now that the naming is
corrected, either syntax works (I've run it both ways). I'll stick
with [ListMaster allObjects] because it's cleaner. I had found on
example online where they used [[ListMaster class] allObjects]. I
wasn't clear on the distinction, but I was willing to try anything at
that point.