Finding this note about %parents% (with an S) instead of %parent% is exactly what I was looking for! But I just noticed an odd error. If one goes back to the settings page after changing the Custom Permalink Structure field, that field is ALWAYS empty, or more specifically, that field always has the placeholder text in it, no matter what you just saved that field as. SO it always has %parent%/%slug%/ greyed out in it, even after I just applied %parents%/%slug% (added that S on parent and removed the trailing slash).
Shouldn't that field always show what the current setting is?
Shouldn't that field always show what the current setting is?