That is a better explanation than I got from Anthem.
I just gave up on CEC because I (and especially my
wife) want to control my LG TV and the Anthem
independently.
I also, gave up on eARC. I have my Directv DVR
and Oppo connected directly to HDMI IN on the
Anthem and optical audio out from the TV. This
is not ideal as I would probably be getting better
sound quality using HDMI cables.