"I would add that many of these teachings are also present in churches that are not Catholic or Orthodox but equally ancient -- the Armenian, the Coptic and Ethiopian churches for example."
Well, they really are part of the Church anyway, the Monophysite language misapprehensions to the contrary notwithstanding (although the Copts can get pretty huffy sometimes!).
Actually it is pretty interesting reading about the debates between the usage of terms like hypothesis, Theotokos etc. I guess it's all Greek to me ;-P