--link-dest, update permissions w/o creating a new file

[Matthew Monaco]

I like the behavior of first doing:
cp -al /backup/old /backup/new
rsync /source /backup/new

This way permissions will be updates throughout all snapshots (I really
don't want multiple copies of my entire music collection if I decide to
make all songs group readable... etc)

Has anyone come up with a way to do this using --link-dest?

Matt