It's for the Pope and no one else to be the ultimate arbiter of what is and what is not Traditional. In this passage here, routinely distorted by R&R, Vatican I teaches:
For the Holy Spirit was promised to the successors of Peter not so that they might, by his revelation, make known some new doctrine, but that, by his assistance, they might religiously guard and faithfully expound the revelation or deposit of faith transmitted by the apostles. Indeed, their apostolic teaching was embraced by all the venerable fathers and reverenced and followed by all the holy orthodox doctors, for they knew very well that this See of St. Peter always remains unblemished by any error, in accordance with the divine promise of our Lord and Savior to the prince of his disciples
So Vatican I teaches that "
the Holy Spirit was promised to the successors of Peter ... so that they might ... by his assistance ... religiously guard and faithfully expound the revelation or deposit of faith transmitted by the apostles"
.This is the very role of the Papal Magisterium, to expound or explain the Deposit or Faith (in Scripture and Tradition) ... it's not your job or your authority, Stubborn et al.
Now, R&R warp the expression that the Popes were not promised the assistance of the Holy Spirit to "make known some new doctrine" into meaning that, "If the Pope makes some new doctrine, he doesn't have the assistance of the Holy Spirit." But this passage merely distinguishes the Magisterium from the initial Revelation or Deposit. At no point does the Pope add to the Deposit, i.e., is not adding to Revelation, but is merely expounding the Revelation, but the assistance of the Holy Spirit is promised in order to have him do it "faithfully".
Archbishop Lefebvre reiterated this teaching, that the promises of Christ for the Papacy preclude the destruction we've seen with the Conciliar Church. Do you reject or refute Archbishop Lefebvre?