You should check out the writings of a bloke called "Origin". Now as i recall he was writing within a century or so of Jesus's death and was considered for saint hood. Anyway, he went on about people taking much of the new testament too literally and totally missing the point which was intended. Not sure the writers of the Gospels had a debate on embryos in mind when the penned that one. Something much deeper is actually going on.
I have read Origen....And I have just skimmed the book "On First Principle", chapter 2 "that many by not understanding the scriptures spiritually and by badly understanding fall into heresies"
It is a short chapter. And I would agree with your assessment of the situation with embryos. I brought it forward as preston seems to be an advocate of the "embryo" theory. And I am trying to imagine how he comes up with Jesus being fully human, but not of human ancestry...?