I doubt there is a way to "pass through copyright" on Youtube. Mirrored videos might delay it, but it could still be visually detected by someone on YT and they could report it.
Well, I do have a theory as well. My guess is that you can post any video you want while being protected from it being taken down. Thing is, it was DarkHououmon herself who gave me the information that blossomed into this idea: Why not just upload movies but make them private links? You know, only sharable to those you trust who would never report you. For example, uploading a LBT movie, making a private link, then posting it on the forum here would shock me if you were reported. I’m pretty sure that youtube doesn’t waltz around in their archives checking private-link videos to see if someone uploaded something under copyright. And that’s my two cents on this issue.