Aha! There I agree with you. If a Pope ever says anything against Scripture or Tradition ex-cathedra and tries to bind the faithful to it he would not be Pope. This is the protection we have from the Holy Spirit. He would either be an antipope, imposter, etc. However if he just says something such as "There is no Hell" over and over in public then we are not to follow him in that principle. Theologians agree that we have had Pope's who have said theologically incorrect things. They have never tried though to bind the faithful to their incorrect ideas. That is where the Papal infallibility comes in.