I seem to remember that "bit peeling" was designed into Ogg Vorbis audio from early on, such that the data stream could be encoded in order of decreasing audio

I seem to remember that "bit peeling" was designed into Ogg Vorbis audio from early on, such that the data stream could be encoded in order of decreasing audio perceptibility such that data frames could be truncated at certain points and you'd get a good lower-bitrate stream. However, I've never read of a Vorbis encoder that actually encoded that way.