By comparable terms, CLF's management make the Rio guys look brilliant.
CLF’s management is more inept and has had more individual screw-ups than RIO’s management; however, RIO’s one big screw-up (overpaying for Alcan) was so colossal it outweighs everything CLF has done wrong in terms of shareholder-value destruction.
Moreover, CLF still has a decent chance to be acquired at some point, but I doubt that anyone would pursue RIO.