It depends on some premises, but the reasoning is sound. You're fine to disagree with the premises. And like I said, it's not new, that explanation of the Trinity been around since at least Thomas Aquinas, and implied in the Gospel of John. No, not objective at all. Angels are not minor deities. Is the messenger of a King a minor King? No. Jesus is not a demigod. He is not born of a union between God and a woman. Jesus is not half and half. He is fully human and fully God, the incarnation of God. Jesus is God. Mary is not a deity. She is a woman, very righteous in her own right, who gave birth to Jesus. No, it's not polytheistic. There is only one God. If a candle is placed next to a mirror, does its reflection mean there are two candles? No. And I wasn't indoctrinated throughout my life. Again, Jesus is not a demigod, he is the incarnation of God himself. A more correct analogy would be if Zeus decided to be conceived, born, live, suffer, and die as a human.