yeah. it's a different take on the "medievel England" legend we all know. they take the look that the legend of King Arthur & the Knights of the Round Table was actually based partly in truth on a real person only the story took place in about 450AD versus the middle ages. the time when the Romans were trying to conquer the world.
By that time the Roman empire was on it's last legs.
Maybe he thinks it was realistic because the middle ages and the roman empire over lap a little and therein lies Camelot. Or maybe he thinks it's a documentary.