What do you figure they would actually see? Probably not anything that looks like the original video, I would guess
I don't know. I took apart and fixed some VHS tapes back in the day, but I never thought to mess around and stick one in backwards. I didn't expect them to get any audio out of it, but amazingly it looks like they did.
Newer VCRs were better for stuff like automatically correcting tracking errors, but if you had a slightly damaged section of VHS, the old VCRs would let you watch the flawed video, while newer ones would say "Nope" and give up immediately. The quitting was way more bothersome than the video errors. RLM's too-smart VCR didn't even try to show what garbage an upside down tape looks like. It gave up and quit before even making one single attempt to entertain us.