The problem with "R + R" is that its a really broad term. But TBH, if we're talking particularly about the "SSPX Resistance" position, to be honest I agree with you. I've tried to avoid saying too much about it here, both because this is an SSPX Resistance forum to some extent., and also because I'm a new convert, but I agree that that position is not really internally consistent. I think the regular SSPX, and Sedevacnatists each have a more consistent position than the "SSPX Resistance."
But that's the question. Is "R + R" just +Williamson's "have nothing to do with Rome at all?" Or does it also entail +Lefebvre? Does it include +Fellay? Does it include FSSP types who do believe in hermeneutic of continuity at some level, but yet disagree with the way the modern hierarchy interprets and applies the council? Does it even include John Paul II type Catholics who don't like Francis? What exactly is resisting? Recognizing has a fairly obvious definition, but resisting doesn't.
R&R certainly is a broad label, but it suffices. Remember that in their effort to justify their position, the sedes often quote +ABL, same as they quote numerous of the popes, saints and Fathers, none of whom were sede btw. Now consider what the force of such quotes would be were they to quote sede popes, or sede saints, or sede Fathers, now *that* would be something. But there are no such authorities to quote.
The second "R" means simply, resisting the pope's errors. Recognize that he is the pope, resist his heretical acts and teachings, just as we would resist Billy Grahm's teachings, or Martin Luther's teachings, or any other heretic's teachings.
This position is unacceptable to sedes because they wrongfully believe that a pope, speaking as pope, cannot teach or fall into heresy, some believe that even as a private individual he cannot fall into heresy, even many non-sedes believe or are confused, thinking that this is a doctrine or dogma or otherwise somehow taught by the Church, when the reality is, this idea was only taught by some theologians during the past century or two. But because they believe it to be a teaching of the Church, they condemn R&R for the second "R".