This was done a while ago, but I forgot to close the issue.

Perfect. :-)

Fixed in r4509. Gabi, can you have a look that I changed the things related to
the option parsing in the correct way?

That option doesn't do any good -- our search algorithms shouldn't look up the
same state twice anyway, since the responsibility for spotting duplicates is
somewhere else. Moreoever, it apparently was always false in the old code
(before the new command-line syntax) anyway.