my main issue here is still that until the Church in some way *tells us* that Francis is a manifest and formal heretic and thus has fallen from the pontificate, its just a theory, at best.
To a point it is just a theory. So, for instance, Archbishop Lefebvre speculated too about other possible explanations. Was Paul VI replaced by a double? Was he insane? He dismissed those. I don't think he broached the subject of whether Paul VI was blackmailed on account of sodomy (a real possibility). In that case, his acts weren't free.
That's why I don't really care how one lands on the Pope issue. What I care about is this ...
Catholics cannot say that the Catholic Church has done all this evil. That's contrary to the indefectibility of the Church. Either these things that have been done were not evil (conservative Novus Ordites) or else it was not the Catholic Church doing them (sedevacantists) ... for whatever reason, or with whatever explanation, the explanation being theoretical, as you put it, and just an opinion.
Here's my take. I do not recognize the Conciliar Church as the Catholic Church because it lacks all the marks of the Church: it's got corrupt doctrine, corrupt Sacraments, a corrupt Mass, corrupt Canon Law, corrupt moral discipline, etc. etc.
This is where there IS in fact a role for private judgment, identifying the Church as the one founded by Our Lord. Vatican I taught this in the lesser know teachings of the Council (overshadowed by papal infallibility), that the reason plays a role in assessing the "motives of credibility" that lead one to subjecting oneself to the authority of this Church. I see these "motives of credibility" to be completely absent with the Conciliar Church, so I cannot recognize it as the Church. As one of the sheep, I do not recognize its voice as being that of the Shepherd.
Beyond that, if someone wants to say
papa haereticus ipso facto depositus or
papa haereticus ab Ecclesia deponendus (as Fr. Chazal does where he stipulates that they lack authority), I really don't care, as Catholics can licitly hold either opinion. Heck, I'm OK if someone wants to say that Paul VI was replaced by a double, or was blackmailed for sodomy (not sure about the other V2 papal claimants). The only thing I'm NOT OK with is to say that these evils were perpetrated on the faithful by the authority of the Catholic Church. That is absolutely impossible. And, to be honest, I'm actually fine, in principle, with the conservative Novus Ordite assertion that these things were NOT evils at all, but just need some interpretation with the hermeneutic. Now, I don't buy it, but I can't say that it's an intrinisically un-Catholic position to take ... as many articulations of R&R are. I'm MORE AGAINST THESE BAD ARTICULATIONS OF R&R than I am against those conservative NO Catholics who try applying the hermeneutic of continuity to V2, etc.
That's why I have said that I am not a dogmatic sedevacantist. I am a dogmatic indefectibilist.