[driax]

FLAC would probably be a bad example, since it is lossless. It makes fewer assumptions about the content of the audio file, since it anyway has to encode all of the noise and minor stuff. Making too many assumptions of the content would only necessitate a facility to introduce specified noise into the audio later. Which I can't imagine would be both fast and small.

[DebianUser]

I don't think it has much to do with the fact that it is lossless, but rather that it does not compress in a suitable way. In the scheme of things outlined by GGP. Whether such scheme implies lossy is a question that needs to be demonstrated imho.