Originally Posted by Cyclosaurus

Unfortunately I've given up believing that visibility is somehow the key to safety. Your experience demonstrates the futility of that. I think many (not all, but enough to matter) drivers are operating in "lizard brain" mode while operating a vehicle. Their brain automatically filters out anything that's not a threat to them. The bike and trailer, while quite visible (even the driver admitted it), posed no threat, and he automatically and subconsciously screened out the information, only to be surprised that you were still there. The confused, can't-get-the-story-straight interaction you got was the result of him having seen you but his lizard brain telling him to ignore you.