There are a couple of SCCS projects which are just barely outside of your epistemological discussion. ;)
CSSC, which is the GNU project's implementation of SCCS. It uses git: http://www.gnu.org/software/cssc/ . CSSC is meant as a stepping stone to migrate existing SCCS projects to some other version control system.
Sun released SCCS in 2006. A couple of forks exist. One is the Heirloom project. If I read http://heirloom.sourceforge.net/devtools.html correctly, they maintain their version of SCCS using CVS.
CSSC, which is the GNU project's implementation of SCCS. It uses git: http://www.gnu.org/software/cssc/ . CSSC is meant as a stepping stone to migrate existing SCCS projects to some other version control system.
Sun released SCCS in 2006. A couple of forks exist. One is the Heirloom project. If I read http://heirloom.sourceforge.net/devtools.html correctly, they maintain their version of SCCS using CVS.
These are unlikely to affect your vote.