Nah, sedeism never really tempted me, I mean, I thought about it when I was a lot younger, but if I was going to, I would have gone along with (then) Fr. Sanborn and those who he took with him in the 80s. As it was then it is now - no matter who you are, there is no reason to be the least bit concerned about the status of popes.
I agree that the actual legal status of the V2 papal claimants doesn't matter, but the Papacy and Catholic ecclesiology do matter. So the real danger with R&R is sliding into a schismatic, Old Catholic, even Orthodox metality about the nature of the Church and the Papacy. Catholics must be very mcuh "concerned" about that. If we're wrong and are sliding into Old Catholicism, then we will lose our souls. Yes, it matters. Now, whether the V2 papal claimant has been impounded, deposed, formally stripped of authority while retainig material office, blackmailed, drugged, replaced by a double, impeded by the true election of Cardinal Siri, those are details that indeed do not matter and are not for us to solve anyway. Retaining the Catholic faith on the other hand, yes, that matters.