Well, I've watched people who are very good at ballroom rumba dance it, and while I wouldn't want to suggest that it is unmusical, or unemotional, but it is certainly very different than its street relatives. I would even go so far as think "they got this from the son?" when I see ballroom dancers do their rumba. Again see the analogy to walking. Just because the base mechanism is the same doesn't mean they are totally similar movements. It may well be fairly easy to go from one to the other if you are good, but the differences are there, and they are obvious. All you have to do is look!