I see. I believe what allend is trying to say is that the only way to say that Mary is mother of the man Jesus but not the mother of the Divine Jesus - as you seem to be saying - is to say that Jesus is two Persons. He's not saying that he believes this himself. And I'll deny to my last breath, God willing, anyone who attempts to say that Jesus Christ is not One Person, fully God and fully man, the Second Person of the Holy Trinity.
I say he can be one person with a mortal earthly mother. Your interpretation takes more faith.