I think there's an amount that they can overdub and retrack and still have it considered live. A famous example would be where Frank Zappa decides that a live solo of his is great, but it sounds too thin. So he gets Steve Vai to replicate it note for note and mix the track with it.
... and that's all I have to say about that.
[U]ALL[/U] generalizations are [U]WRONG[/U]
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