CathInfo.com

Pertinacity deals more with PERSISTENCE than with sincerity.  We can't judge the internal forum, only the external ... which is why the theologians discussing the possibility of a Pope vacating the See due to heresy speak of "MANIFEST" heresy.

Another thing to consider (at least for me) is how do we set about to prove the pertinacity of the Pope's heresies? For it is one thing to state that he has professed heresies but another to consider how pertinacious he is. Does he [the Pope] know exactly what Catholic doctrine is and subsequently assents to its contrary? Obviously, I don't mean to exonerate any of the Conciliar Popes but it seems that this issue is simply left to the judgment of every person (and this explains also why there is such a wide-range of opinions regarding the various points in the sedevacantist world).

Also, does a legal procedure even exist when we are to set up judging the man who occupies the See of Rome as outside the Church and subsequently not the Pope? It seems the sedevacantists don't even consider this but state that it is simply Divine Law that guides them. However if that is the case then what is the point of canon law?