Matthew said:
I asked this same question to a sedevacantist nicknamed "gladius_veritatis" about 9 years ago. He basically answered, "nothing, really..."

In my post/question, I elaborated on a few details of what it means to be Trad, for example: daily rosary, no meat on Fridays, practice fasting/abstinence on Ember days, practice Advent during Advent, ladies wear skirts/dresses, and so forth.
I agree that there is no practical change for an existing trad to make, if he were to become a sede overnight.  I just wanted to see what the actual sedes on this site thought.  Judging from the lack of responses, I guess the answer is the same as you received "nothing, really...".

 
A few things would change. The new sede would obviously switch to a sede chapel, plus get educated through the new pastor to make sure he/she has the correct understanding on the situation in the Church. Plus the new sede would avoid any other chapels that don't teach Catholic doctrines correctly or that have doubtful clergy. That's the routine I have always seen. Most else would probably remain the same.
 

A few things would change. The new sede would obviously switch to a sede chapel, plus get educated through the new pastor to make sure he/she has the correct understanding on the situation in the Church. Plus the new sede would avoid any other chapels that don't teach Catholic doctrines correctly or that have doubtful clergy. That's the routine I have always seen. Most else would probably remain the same.
 

You assume that Sede chapels are available 1:1 with recognize and resist chapels. That is simply not true, so it's a foolish assumption to make. Perhaps a few areas of the country have a wide variety of chapels available for all Traditional "tastes", but such places are few and far between.

For most of the country, sedevacantists chapels are about 8% as numerous as recognize-and-resist chapels, if that.
So in most cases, the new sedevacantist would continue to attend his SSPX chapel (although today, since the SSPX has become the neo-SSPX and soon becoming "FSSP II: The Revenge", this might change...)

Remember, the majority of sedevacantists don't adhere to Fr. Cekada's peculiar "allergy" about being "una cuм" the putative Pope in Rome. His position is a fringe novelty, even today.

But for these Sedevacantists, the classic SSPX position -- basically the Resistance -- is one thing, but the Indult is whole different ball of wax. When you're talking about the Indult, you have issues with shared facilities, priestly/episcopal validity, etc.

I (a Resistance supporter) personally don't consider the Indult to be an option. In other words, I stay home if that's all that's available. The Indult is just too doubtful for me, plus I won't go anywhere that shares a facility with the Novus Ordo.

1. I wouldn't say that "one view on traditional Catholicism is as good as another", but I WOULD say that we can't know the truth with certainty. There might be a "favorite" from Our Lord's point of view, but as I've said a hundred times, Our Lord hasn't personally appeared and weighed in on the issue.

The best you and I can hope for is to make a good, prayerful, informed PRUDENTIAL decision. Our decision will only be as good as our prudence.

2. We know there is one true Church: the Catholic Church. We know this with the certainty of Faith. So every other so-called religion is objectively wrong, period. But we do not have ANYTHING CLOSE to such certainty regarding which Trad group is best. We're talking about lifeboats here, not the Church. We all agree that the Catholic Church is the One True Church. So the arguments against false ecuмenism do not apply, when discussing the various Trad flavors.

Therefore it is ERRONEOUS and even EVIL to pretend that only "my" trad group is legit, and everyone else is objectively in error and/or mortal sin, just as we consider all the protestants to all be in error and/or mortal sin.

I know that you are arguing that "we can't know the truth" regarding the trad groups, but my argument is that we can know the truth without our Lord appearing to us. We simply need to confirm Francis has taught heresy. No one is accusing anyone of being in mortal sin or outside the Church - the only question is whether heresy has been taught. Do you have any doubts that Francis has taught heresy? That is the only criteria the faithful need to focus on as I see it.

First, the SSPX accepts Novus ordo priests into their ranks without conditional ordination. The new rite of ordination is doubtful at best, so these "priests" are providing doubtful sacraments, and they are scattered all throughout the SSPX. I would switch for this reason ALONE. Second, the SSPX tells their congregations to disregard the man they think is the Pope, which is schismatic by definition. Another reason to switch. Third, the SSPX teaches General Councils (always infallible) can teach error. I could go on.
 
You admit the Church teaches a heretical Pope loses membership in the Church, then in the same post you say the current crisis is a mystery with no satisfying explanation. Major contradiction. If you know the Church has taught this, why are you resisting the Church? Francis has taught even against the Natural Law which no one can claim ignorance of, so this can only be labeled formal heresy. This means the teaching of the Church takes effect; Francis has lost membership.

You also say both R&R and sedevacantist positions "have their weaknesses". ONE and only ONE position has to be true, which leaves any others false. 2+2=4 is true, and all other answers are false, but no one in their right mind would say, "2+2=4 has its weaknesses" - it's either true or it's not. If R&R is true, sedevacantism is false, and vice versa.

Regarding the first paragraph - what you are talking about is not strictly related to sedevacantism and becoming a sedevacantist. One can have doubts about the new rite of ordination and be a sedeplenist. Or one can simply attend these SSPX chapels which have validly ordained priests. If a priest has unquestionable ordination I still do not see a necessity of switching chapels after one becomes a sedevacantist. Regarding indefectibility of the Church - yes, they are in error, but one can simply disagree and keep attending SSPX/Resistance chapel. I reject R&R position, yet I have no problem attending the SSPX chapel, because I know that SSPX teaches this error in good faith and otherwise provides solid Catholic teaching and valid sacraments.

As to the second paragraph - yes, a heretical Pope loses membership in the Church, but one needs to prove he is a formal heretic, not just a material heretic (which you can't do). And yes, the crisis is a mystery and no one has perfect explanation. You conveniently ommited the major problems which I pointed out and which are well known, including ecclesia-vacantism - according to sedevacantist scenario there are no more valid bishops with ordinary jurisdiction and all episcopal sees are vacant, which is impossible, since it would mean the end of Apostolic succession. Thus, your position has just as serious problems as R&R. Thinking that sedevacantism provides a complete and comprehensive explanation of the current crisis is a delusion.

Regarding the third paragraph, you speak as if there are only two positions - R&R and sede. There are many others, such as sedeprivationism, Siri thesis and "hidden" Pope etc. Nobody has all the answers, God will reveal it when He wishes, and untill then we are not accountable for explaining what we can't fully explain and what has no precedence in history of the Church.

I never denied any of that - to the contrary, I absolutely agree, which is why I'm not a sedevacantist. A private judgment of laymen in a pew is insufficient to determine with certainty of faith whether a Pope fell into formal heresy - that could have happened and there is indeed a very strong possibility that V2 claimants are/were not Popes, but currently we can't know that for sure.

Understood.  I was elaborating on your statement that it's clear that formal heretics cannot be popes (since they're not Catholic).  I was just explaining why that statement is not as obviously applied to concrete situations as the sedevacantists pretend.

Perhaps it would be well to a little history behind Tradhican's attitude, and irrationality here. He has declared himself to be another Ladislaus in his views, so he highly admires him. Ladislaus has, 2 months ago, written this about me:

"Laszlo Szijarto declares Nado/Bumphrey to be heretically depraved filth.  May the search engines record this for posterity."

Why?  Essentially because I have been promoting a subjective in all its detail, from two separate books approved at the turn of the 20th century by two separate Archbishops of the United States. As well as another subject I found in 6 different imprimatured books of the 19th century.

So, Ladislaus won't accept those approved Catholic books, and because I won't listen to him telling me I shouldn't either, I am "heretically depraved filth"!

By debating with someone online we empower them, acknowledge them.

All you are doing here is creating your own excuse why you don't fight error when you ought to be. The Church demands we fight error, and there is no such thing about "empowering" the person by fighting his error publicly. If you don't feel personally capable of crushing an error, that is the only reason that can excuse your obligation to fight it.

Unfortunately, we can't see them, so it takes a while to get to know them and during that time that we respond to them out of charity to them and others, they  get puffed up.  "I'm important, Matthew and Ladislaus responds to me."

As if you yourself only respond to people you personally know? Just a double standard you have.

Everyone who posts something who thinks he is helping others thinks he has something important to say.  I am the same. The double-quoted citation you gave is a lie. You should never use double-quotes unless you are actually quoting someone. I never intimated, ever, that I myself am important just because I, too, have some important things to say. 

Haha.  Nice analogy.  But...Is this a coded message telling me that the real pope is hiding in Wisconsin?  Is that where we find the "real cheese"?   :ready-to-eat:

Thanks. My post was somewhat of a joke and only partially serious. But if it was meant to be taken seriously, I think it would be a message that there is an alternative cheese that is real cheese and tastes good and does not have any holes. Of course that would be the cheese of the true Pope in exile Gregory XVII.

Regarding indefectibility of the Church - yes, they are in error, but one can simply disagree and keep attending SSPX/Resistance chapel. I reject R&R position, yet I have no problem attending the SSPX chapel, because I know that SSPX teaches this error in good faith and otherwise provides solid Catholic teaching and valid sacraments.

 
The Arians taught a SINGLE error in good faith too, and St. Athanasius and other clergy of his time insisted Catholic stays away. The Church has taught this repeatedly, for example:
 
"Since heresy, and any kind of infidelity, is a mortal sin, they also sin mortally who expose themselves to its danger, whether by their association, or by listening to preaching, or by their reading." - St. Alphonsus Ligouri