Can I remove stg sync --undo ?

I'm preparing a patch that removes all the old --undo flags, and
discovered that stg sync has an --undo flag backed by
stack.undo_refresh().

Is it OK if I remove it? "stg undo" will allow you to undo the whole
command, or, in case of conflicts, either the whole command or just
the last conflicting push. But it does not allow for undoing the last
refresh (whether it succeeded or not). I don't know how refresh is
used, so I can't really tell if "stg undo" is currently insufficient.

-- 
Karl Hasselström, kha@treskal.com
      www.treskal.com/kalle