David's idea of using the dpkg status files to aid in backups got me
to thinking: There's this feature of dpkg where older packages can be
partially superceeded by newer packages, but I don't think dpkg
currently tracks which package has superceeded which.
If I understand correctly, there's an order imposed on package
installation by this feature. To use dpkg installation to recover a
system, there would need to be some record of this order.
Unfortunately, I don't have access to my debian systems at the
moment, so I have to ask: is this feature present in the existing dpkg