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What I'm hearing is that the Quran-kisser's and Mass-wrecker's papacies aren't even doubtful.

That would be what you are hearing from the sedevacantists, Marulus, who know for certain that he is not Pope and make a definitive judgement which obliges the Catholic conscience.
What did St Robert Bellarmine mean by this phrase about a doubtful Pope? What was he referring to? How has the Church applied it? Is it a dogmatic Catholic teaching?
Archbishop Lefebvre admitted a doubt. He said he could not have metaphysical certainty. He said 'I don't know'. He went on to say (all in 1983 in response to the departure of the nine) that 'it is a very great presumption' to presume that he remains Pope. That was in English, which he struggled with, but his meaning was that it is a very good presumption.
That is what separates the sedevacantist from ABL and R&R. The sedevacantist knows, whereas R&R refrains from a definitive judgement because it is an entirely new situation in the Church and it is not certain that we can make such a judgement.

Lefebvre isn't the guide of faith and principle of unity given to you by God, that would be the Pope. YOU chose Lefebvre,

No, God chose him, I didn't even exist.
In every great crisis God has raised up a saint to guide Catholics who want to remain faithful.
In the greatest crisis of all, according to you, He left us orphans.
God chose ABL for his mission in the Church and Catholics the world over recognised in him a true and faithful shepherd, one preeminently suited to guiding us along the sure path of the Popes and the Church. But you know the Popes and the Church better than he.

I’m going to say something really controversial in Tradition right now but I don’t think Archbishop Lefebvre will ever be canonized as some great saint by the Church. I believe he led a heroic life and did great things. I believe that his books should be sold in churches around the world. I believe many good things about Archbishop Lefebvre. But Plenus Vehementer has raised him to a shining star guiding the path. I think we need many archbishops like him. But not one in particular that is elevated to a status of being the greatest archbishop ever and that his position in 1990 is wheee we should stand locked in time forever. Over thirty years ago into this crisis. If we stay locked in the mindset of 30 years ago we indefinitely further this crisis as if we await a miracle from God. I disagree with this approach. 

Also, there is the signature of Archbishop Lefebvre on all the Vatican 2 docuмents and his claim that he didn’t sign those docuмents. I’m willing to accept that he signed to acknowledge his presence there and nothing more as a sort of roll call. But there was a ton of controversy regarding the signature on all Vatican 2 docuмents and the claim that there was not. It’s not guaranteed that Archbishop Lefebvre will ever be canonized. He did many great things for Tradition. That is undoubtedly true. If we repeat forever that “now is not the time” to say that we do not believe the pope is valid. Then we accept any nonsense from the non-Catholic sect in Rome. Including women priests and ɧoɱosɛҳųαƖ marriages. If you do not think that that is right on the horizon then you haven’t been paying attention.