Yet, you have no problem with the same "joe plumber" recognizing heresy in nothing less that an Ecunemical Council and rejecting as sacrilegious a Rite of Mass promulgated and celebrated by the Sovereign Pontiff.
Precisely. I too have the objection to SVism that "Joe Plumber" cannot be in a position to recognize deposition. That would lead to chaos in the Church. Yet the same is true of "Joe Plumber" rejecting V2 in the first place, as you point out. That's why I call my position "sededoubtism". We can question, formulate a positive doubt, but that's as far as we can go in principle. I knew a guy who rejected Pius IX, and a few who rejected Pius XII ... based on their own lights. Where does that stop? And R&R claim that "Joe Plumber" can reject the teaching of an Ecuмenical Council.
Recall the continuum I laid out on the path to sedevacantism. I believe that we're n a
Papa Dubius stage of the process ... .which suffices to strip him of all formal authority.
So what's the difference between Magisterium-Sifting (R&R) and Pope-Sifting (SVism)? I raised this problem in my 1995 article on sedevacantism. I think that I have an answer, and I'll articulate it later when I have some more time.