I'm not sure why EOs give so much more theological latitude to the OOs than to the ACOE. While they may be a bit further away from us, they're not really Nestorian/Mopsuestian heretics either.
Take a look at their joint declaration with the Roman Catholics.
Link? Quote? Some kind of rabid-OO polemic of "See, I told you, the Leonians and Nestorians are in bed together all along!" (The last one was just a JOKE!)
"The humanity to which the Blessed Virgin Mary gave birth always was that of the Son of God himself. That is the reason why the Assyrian Church of the East is praying [to] the Virgin Mary as 'the Mother of Christ our God and Saviour." -Joint Declaration: http://en.wikipedia.org/wiki/Common_Christological_Declaration_Between_the_Catholic_Church_and_the_Assyrian_Church_of_the_East
"The Orthodox position will declare this: The Blessed Mother did not give birth to His Godhead, which is from eternal; but rather she had given birth to His manhood, at the end of time, still it is right to be called 'the Mother of God,' why? Because He who is born of her is at once God and Man. By way of example: The mother of the President of the United States did not give birth to his presidency, she gave birth to the man; and indeed we call her the mother of the President; and again, the Catholicos Patriarch of the East received his office from The Church, and not from his mother who bore him, and we do call her the mother of the Patriarch." -ACotE Catechism
"The Word of God, second Person of the Holy Trinity, became incarnate by the power of the Holy Spirit in assuming from the holy Virgin Mary a body animated by a rational soul, with which he was indissolubly united from the moment of his conception. Therefore our Lord Jesus Christ is true God and true man, perfect in his divinity and perfect in his humanity, consubstantial with the Father and consubstantial with us in all things but sin. His divinity and his humanity are united in one person, without confusion or change, without division or separation. In him has been preserved the difference of the natures of divinity and humanity, with all their properties, faculties and operations. But far from constituting "one and another", the divinity and humanity are united in the person of the same and unique Son of God and Lord Jesus Christ, who is the object of a single adoration. Christ therefore is not an "ordinary man" whom God adopted in order to reside in him and inspire him, as in the righteous ones and the prophets. But the same God the Word, begotten of his Father before all worlds without beginning according to his divinity, was born of a mother without a father in the last times according to his humanity." - From the Common Declaration
Hmmm. That's a very interesting paragraph, that multiple times uses the phrase "one person." I hadn't previous read the RC/ACoE Declaration because, obviously, it has nothing to do with us...perhaps I should...
I've never read it either, but clicked on the Wikipedia link Nicholas provided. I find it interesting he left this rather large chunk of text hidden behind the link, and only quoted what he did.