The Church has never taught that the Pope is an all-purpose oracle. The level of authority behind any papal statement--- whether it's something as weighty as an Apostolic Constitution or an Encyclical, or something as mundane as a weekday Homily from Domus Sta. Martae or remarks at a Papal Audience --- depends on the teaching's dogmatic history, and the intention of the pope.
Not everything the pope says is an "edict." Not even everything he says in an encyclical is an "edict". Sometimes it's just a pastoral reflection, sometimes a passing opinion, sometimes even an off-balance, fragmentary and garbled verbal output worthy of "edit" or "delete".
I think Francis would be the first one to admit this. One of the men he just canonized, St. Pope John XXIII, once said, "I am only infallible if I speak infallibly but I shall never do that, so I am not infallible".
I love pope who can handle a nimble tautology.
Actually what I am addressing is who gets to determine the difference. It is my understanding that the Catholic laity is not authorized to make such decisions, and that they are told by the clergy what the applicablelevel of authority and interpretation of any Church teaching, or Papal action or statement, is. So in a functional sense it doesn't really matter what the laity thinks of the difference between Papal opinion and magisterium, because they don't have the authority to implement their decisions on the subjects.