Well, the founding documents were all by, and about, white men. Nothing about their wives, slaves, the native americans who were in their expansionist way, etc.
We've had a Civil War, Women's Lib, and are currently in a scandal involving a lobbyist for some of the tribes. None of this could be deduced from the founding documents, and the idea that reading them will greatly inform anyone about how politics works today is just silly, or idealistic. And the idea that we SHOULD behave the way Madison dreamed we might (absent all those ignored people) in the agrarian pre-industrial world he lived in is even worse!