Ladislaus...  For the first time ever, I have read an explanation of the Siri Thesis that makes sense.

As for the topic.  The Conciliar sect is a non-Catholic religion.  It can no more give the Catholic Church a pope than a council of Lutherans, Baptists, Anglicans, Muslims, Hindus, or any other group.  We will have a new pope when the sedevacantist bishops politically unite and choose one.

Agreed about the Conciliar False Religion.

That's why rather than dogmatic sedevacantism I advocate something I refer to as "dogmatic indefectibilism".

AND, if you read Vatican I, the ONE PLACE where private judgement enters in is in ascertaining the identity of the True Church of Christ.  We rationally evaluate the "motives of credibility" preliminary to acts of faith.

This is beautiful because no one is required to be a theologian with an advanced degree to determine whether there are heretical propositions in Vatican II or not.  God made it this way and FORCED the Conciliars to be exposed to all those with eyes to see.  So God did not permit them to put on so realistic a "wolf costume" as to fool everyone or to mimic the voice of the Church.  He forced the infiltrator heretics to put on a crappy wolf costume with gaps in it so that those with the eyes (of faith) to see, could see through it.  That reminds me of when my kids were little and they went to see these people dressed up as "Easter Bunnies" somewhere and one of my kids could see through the gap in the costume and see some guy with a beard under there.    That's the Conciliar "wolf" costume that God made them put on, not allowing the deception to be so complete as to fool those who had Catholic faith left.

Let's say that there had never been a New Mass but the Tridentine Mass was still here, and they didn't start "canonizing" everybody and their uncle and change Canon Law, and the only issue was the teaching oif Vatican II, where maybe there were one or two errors in there.

Would there be a Traditional movement?  No.  It's because God forced them to expose themselves as a New Religion that those with a mere simple sensus fide can I identify it, where the Catholic Sheep know the Voice of their Master, and the Concilair Church ain't it.

When I became a Traditional Catholic, it was very simple, and involved little theology.  I saw the Tridentine Mass and my souls was simply drawn to it by God's grace.  Then I read a book by St. Alphonsus for the first time and came to the conclusion that the faith this man showed in that book is simply not the same faith that the Conciliars have.  You just KNOW on a gut instinctive sensus level that it's not the same thing, like that old Sesame Street game about "which if these things is not like the other."  God made it so the little kindergarteners could figure it out if they just went with their innate Catholic sense.

So, then, we do not recognize the voice of these V2 papal claimants as the Voice of the Shepherd, of Peter, of Christ, and so we do not submit.  There's no Magisterium sifting nor pope sifting, just that simple realization.

Unfortunately, SVism tend to elevate the SV conclusion to dogmatic certainty because one of the premises is dogmatic, but you can't do that if there are other non-dogmatic premises.  Now, MOST R&R do reject SVism by rejecting this dogmatic premise, since it's true most of the time, but one CAN hold an R&R position that doesn't deny the dogmatic presence.

Let's say, for instance, you think that Montini was the legitimate pope but that he was locked up in a dungeon, drugged, and replaced by a big-eared crooked-nosed double.  You might be right or you might be crazy ... but you're not denying the dogmatic premise.  That's where I actually believe +Lefebvre was, since he explicitly affirmed that, yes, "I agree with you [=the sedevacantists]" that the Holy Ghost protects the papacy and prevents it from destroying the Church like this.  He then just went on to prevaricate about possible reasons how this could have happened, e.g. blackmail, the he was drugged or insane, etc.  He dismissed those and said SVism is possible, but can you dismiss the alternate theories with the certainty of faith?  Of course not.  Consequently, you cannot press the SV conclusion with dogmatic certainty.  It's definitely the MOST LIKELY scenario, more than the Montini double, but it's not dogmatically certain.  So IMO that's the mistake of dogmatic SVism and why I adhere to dogmatic indefectibilism.

I can quote theologians who teach contrary to this 

Please do.

I am glad I made this thread.

Okay, so what about the material-formal thesis (sedeprivationism)? It doesn't rely on any personal heresies of the conciliar papal claimants. Nor does it need to speculate on the events of the Conclave.

Ann Barnhardt removed the sede vacante banner. Micheal Matt is scolding anyone who is even remotely suspicious of Prevost, let alone something more. Taylor Marshall pledges full submission. They are all flocking back in after being let down by Bergoglio. It did not take much or long. One can only wonder when the bigger fish like FSSPX will be "fully in" too. That will leave only one undesirable group out there to "spoil the party", of course the mean bad ol' sedes.