Thank you so much for posting this, Terry. I'm a big fan of Ehrman, having read two of his books. His "awakening" is interesting because he started out as a conservative apologist but delving into the scholarly side of the Bible led him to realize that it is definitely not infallible.
With respect to Jesus using the divine name, I reasoned with my elder husband this way: If Jesus or his apostles had uttered the Tetra., don't you think it would have caused a tremendous accusation by the Pharisees who were looking for any pretense whatsoever with which to accuse them? And wouldn't it have been a wonderful witness for Jesus to stand up to them and defend his use of the Name and decry the Jewish superstition banning it? And wouldn't it be recorded in the Bible as a stirring testimony of courage? Wouldn't that have been totally appropriate for Jesus? And wouldn't he have been put to death for it, since the Pharisees wouldn't have to cook up a false accusation?
His response: Silence.