I was told that dpkg did not install through a symlink, so I had
to test it. I had done something similar in a Debian Machine whose /usr
filesystem got full before, so I tested it on a slink machine with dpkg
I first mv'd /usr/doc /usr/share/doc then
ln -s'd /usr/share/doc /usr/doc
I dpkg'd --purge a package and its /usr/doc directory got removed
I apt-get'd install it again, and there it was, the /usr/share/doc
entry, both trough the symlink.
So, what is the problem on using dpkg trough a symlink? Specially
when it is /usr/doc ? I agree that making this move in a upgrading-system
is not simple, because moving an entire directory tree is not a simple task
(without running the risk of losing part or all of /doc).