Well, it's useful. Some people are more honest filling out bubbles than they are talking to interviewers, and someone who comes across one way may not actually be that way and might be better for another job. I mean, not to conform to stereotypes, but I wouldn't want an ISTJ doing customer service (no offense to any of them). But management? Absolutely.
I agree that it shouldn't be a qualification type consideration. It might be kind of useful as a management tool though--there's a test at my current place of employment that is uncanny in its ability to describe us and has actually been quite useful when it comes to explaining change (large and small) to different members of the team based on how they're most likely to react.