I never saw anything wrong with the scream. I sure wish our Republican politicians had that much spirit! Seems the Demoncrats are the ones that object to it.
The reason that the scream was trouble for Dean was that he was rightfully thought of as a hot head, unstable, and liable to explode at any moment. So when it happened it just confirmed that the guy was unstable. A politician of a different reputation and demeaner could have done the same thing with not ill effects.