That's what I'm struggling with. Take the example on the Wikipedia page: I don't know what the faces mean for each judge. Is the judge a jerk? Does the judge take too long with their arraignments? Is this a value, er, judgment on the legal sufficiency of their determinations?

If the primary utility is to be able to quickly visually discriminate values once you know how they're encoded into facial features, then I can see the value, but again you'd have to know the encoding. Or have I missed the point completely?