[charlesism]

    > you can't just CIA-like "ENHANCE" an image to 
    > double its resolution 

I think what you're saying is that if the high frequency information is gone, it's gone? But that shouldn't matter.. we don't need it to be identical to the original. It just needs to sound identical to the original.

If you hit a snare drum 5 times in a row, the high frequency data of each hit will differ wildly, and yet a human won't be able to tell the difference.