-# Make sure that the tweaked dirs times migrate back but nothing else.
-$RSYNC -av --include='*/' --exclude='*' "$chkdir/" "$fromdir/"
+# Un-tweak the directory times in our first (weak) exclude test (though
+# it's a good test of the --existing option).
+$RSYNC -av --existing --include='*/' --exclude='*' "$fromdir/" "$chkdir/"