Thanks for sharing this update. So glad to hear the doctor is not at a loss and feels there are several diagnostic actions to take.

I printed out a lengthy description of what was going on so we didn't have to say too much in front of him
Sounds like an effective plan.

looping conversations always around to something HE wants to talk about...the repetitive nature of his discussions, perseveration on topics
Possibly your son is a politician! wink