Banned Topics List said:
Blatantly disrespectful characterization of any faith, (“Rome is the Whore of Babylon”, “Nazarenes are Holy-Rollers”, “Jews are Christ-killers”, “Muslims are terrorists”) its tenets, practices, or adherents
I think calling sedevacantists “Protestants in fiddle-backs” would fall under this rule. And aside from the topic itself being banned, sedevacantists couldn’t defend themselves even if they wanted to, because their arguments (contra-Vatican II, New Mass, etc.) are also against this forum’s rules. Let’s remember that.
It’s better to pray for others.
P.S. - Regarding the authority of the
Syllabus of Modern Errors:
“The binding power of the Syllabus of Pius IX is differently explained by Catholic theologians. All are of the opinion that many of the propositions are condemned if not in the Syllabus, then certainly in other final decisions of the infallible teaching authority of the Church, for instance in the Encyclical “Quanta Cura”. There is no agreement, however, on the question whether each thesis condemned in the Syllabus is infallibly false, merely because it is condemned in the Syllabus. Many theologians are of the opinion that to the Syllabus as such an infallible teaching authority is to be ascribed, whether due to an ex-cathedra decision by the pope or to the subsequent acceptance by the Church. Others question this. So long as Rome has not decided the question, everyone is free to follow the opinion he chooses. Even should the condemnation of many propositions not possess that unchangeableness peculiar to infallible decisions, nevertheless the binding force of the condemnation in regard to all the propositions is beyond doubt. For the Syllabus, as appears from the official communication of Cardinal Antonelli, is a decision given by the pope speaking as universal teacher and judge to Catholics the world over. All Catholics, therefore, are bound to accept the Syllabus. Exteriorly they may neither in word nor in writing oppose its contents; they must also assent to it interiorly.” –
newadvent.org/cathen/14368b.htm
I’d have to check my sources to comment on then-Fr. Ratzinger’s work, but even then, it might be best to keep it to PM.