Like the very big facet of needing a "convalidation feedback loop" as Lad calls it when dealing with a pope.
"... the Magisterium then becomes subject to a convalidation feedback loop. Pope teaches dogma. Is dogma Traditional? If yes, then accept. If not, then reject pope. Rinse. Repeat. Ultimate arbiter of dogma then becomes the individual's private judgment. "
I disagree with your and Ladislaus' over-simplification of the magisterium. He might be right in his understanding of it, but his explanations on this site are wrong, in my opinion. Here's why I say that.
When Christ ascended into heaven 40 days after Easter, he left the Apostles with ALL the teachings of the Church. After the Ascension, the 'revelation' of truth by Christ was over. So, we can say that after the Ascension ALL of the truths of our Faith were understood by the Apostles. These were passed on to the future by only 2 means - Scripture (written) or Tradition (oral).
Scripture or Tradition contains ALL Catholic Truth. As of 33 A.D., the Church had the FULL Truth. As of 33 A.D., the Magisterium (the teaching authority of the Church) had the FULL Truth. Ergo, after 33 A.D., the Truths of the Faith are set in stone.
Because of these facts, anytime in the future (i.e. post 33 A.D.) when the Church makes use of Her teaching office (i.e. Magisterium), Her job is to re-teach, or clarify those truths which have existed since 33 A.D. The Magisterium cannot teach something new, or make new doctrines, or dogma, etc. All Truths of our Faith were handed down by Christ to the Apostles and the Church's job after the Apostles is to teach "that which has always been taught". Her job is to clarify and certify the Truth when She faces heretics, schismatics and pagans.
...So, in answer to the above quoted sentences, I say:
1. The Magisterium is not subject to a "feedback loop".
2. If the Pope teaches dogma, then He is certifying, by his Apostolic Authority that such a dogma "always existed" since the time of Christ.
3. The question of "is the dogma traditional?" is nonsensical. All dogma is traditional, by definition, because all dogma is Apostolic in origin, as taught by Christ.
4. The question which is not being asked is this: "Is all papal teaching dogma or doctrine?" The answer is "no". There are different levels of authority to papal teaching, just as there are different levels to the magisterium. Those papal teachings which are infallible are doctrine/dogma, for the pope uses his apostolic authority to tell us that such a teaching is 1) to be believed with certainty of faith, 2) because it is apostolic in origin, and 3) came from Christ.
5. All "teachings" which are fallible, are not "of the faith" and not from Christ because they are:
a. not taught with 'certainty of faith'
b. not taught with apostolic authority
c. not taught as binding under pain of sin
Such fallible teachings by the magisterium are not 'dogma' or 'doctrine' and are not part of the Faith. Ergo, if one compares FALLIBLE teachings with previous INFALLIBLE teachings of the Church, this is not wrong, or prideful, but expected. Just as current theologians have debated with theologians of the past, so magisteriums can challenge previous magisteriums.
How is this so? Because the magisterium is not always infallible. The magisterium is the teaching authority of the church, which is the hierarchy + the pope. There are 2 ways the magisterium can teach infallibly:
1. If the magisterium fulfills the requirements of infallibility as set forth by Vatican 1, then it is solemnly
2. If the magisterium teaches "that which has always been taught" and proves it is of Apostolic times, then it is non-solemnly
Yet, if a magisterium of the Church, attempts to teach a truth which a) does not fulfill the requirements of Vatican 1, and b) is not apostolic, then we can be sure it is not from Christ. V2 is an example of a "teaching" which a) did not fulfill the requirements of Vatican 1, and b) has failed to show how its novel ideals are apostolic and Traditional (i.e. from Christ).
So in such a case of contradiction and confusion, how do we know which magisterium is right? By the language used and the 'certainty of faith' with which things are taught, by the 'apostolic authority' expressed and by the 'binding nature' of the teaching. If some "teachings" are missing the 3 above attributes, then they are not part of official Church teaching, and are outweighed by previous magisteriums which taught with all 3 attributes.
V2 did not teach with 'certainty of faith' or 'by apostolic authority' or 'under pain of sin' therefore it did not teach infallibly. Therefore, in any area where V2 contradicts previous dogma, doctrine or infallible statement, then it is overruled, it is superceded, it is anathema.