Excellent point, Dale. I still feel that we need to do something to ensure that each profile has at least one date, but we need to go back to the drawing board to figure out the best way to handle it.
I hate to even think about it, but maybe we need some kind of big bold banner warning that a profile is undated - the same sort of thing we now have for unsourced. That way, we'd at least be dumping them into a category, where they could be systematically addressed by some kind of challenge.