If you watched the Saints beat the Falcons as I predicted yesterday afternoon then you might have seen a play where Chris Ivory was pulled down by his dreadlocks. It would seem that grabbing someone by the hair and slamming them to the ground would be grounds for a penalty but it isn't.

The hair is not considered a part of the uniform and the rules are quite clear. If you don't want to get yanked down by your hair then you need to keep it inside your helmet. I guess fashion means more than giving a defender and extra handle to grab.

You would never see Roger Staubach or John Unitas get yanked down by their hair. If you did chances are their heads would have come off in the process. Here is actual video of the hair rule being brought into play.