Yes, but nothing is saying this has to work for every codec. Since you want to retrieve the files using a special client, you could pick the codec you like. Bu

Yes, but nothing is saying this has to work for every codec. Since you want to retrieve the files using a special client, you could pick the codec you like. But (almost) nothing prevents YouTube from not serving that particular codec anymore. This still pretty much falls under the "re-encoding" case I mentioned which would make the whole thing brittle anyway. But it's indeed cool to think about. 8)