It depends what you mean by dissent I suppose. You cannot not pay taxes they say you owe or not keep its laws. The point is more that the disagreement is over claims for the extent and source of authority and not the authority itself.
According to that link I posted on Vatican II, from a sedevacantist, which claims;
'In order to enable His Church to teach in His Name, he left us, not written works,10 but rather a “living Magisterium” (“the Pope and the bishops in union with Him”) which He endowed with His authority and to which He promised His assistance. This function, the transmission of the “deposit of the faith,” constitutes Tradition (literally, “what is handed down”) and hence the true Church and the Magisterium are by their very nature traditional.11
'The Church teaches and has always taught that there is a divine Tradition, that is the sum of truths which have been divinely revealed to the Apostles, has been handed down without error through the genuine Magisterium of Pastors.12'
Before considering the nature of this teaching authority to which all Catholics owe assent, it is important to stress that it is dependent, not on man, but on God. It follows that the teaching of the Magisterium is infallibly true. If it is not, then it is Christ who has lied to us. Defenders of the post-Conciliar Church often state that the Magisterium of the Church resides “in the Pope and the Bishops in union with him.” Such a statement, while true, cannot be taken in isolation. Used to defend the changes in doctrine, rites, and laws that this new Church has introduced, it becomes a classical case of suppressio veri and suggestio falsi. The statement is true only when the Pope and the bishops in union with him have themselves, in their function as depositi custodies (guardians of the “deposit” of the faith as in 1 Tim. 6:20), in no way departed from or gone against that which was delivered to the Church by Christ and the Apostles.13
The Church has always taught that an individual Pope can stray from sound doctrine in his personal and public life.15 Should this be the case prior to his election, the election is deemed invalid;16 should he openly embrace doctrines that contradict this deposit after his election, and obstinately adhere to them, he would become a public heretic, and as such he would no longer be Pope.17 Such is only logical since, from the moment he publicly embraced heresy with obstinacy, he would cease to be a believing Catholic or the Pope, to say nothing of being Christ’s representative and a “Pontifex” or “bridge” between this world and the next. Th e oft-quoted maxim of St. Ambrose to the effect that “where Peter is, there is the Church” is valid only insofar as “Peter” remains rooted in orthodoxy or “pure faith and sound doctrine.”18 And when he is not, then as Cardinal Cajetan taught, “Neither is the Church in him, nor is he in the Church.”19 Cornelius Lapide, S.J., puts it bluntly:
Were the Pope to fall into public heresy, he would ipso facto cease to be
Pope, yea, even to be a Christian believer.20'
I do not think in the end it is that different from the Orthodox view. The two differences are over the organisation and relative power of the bishops versus the bishop of Rome and in the claim by the Pope to sometimes be technically infallible, as well as practically. However the one seems to follow the other really; if administration of the RCC is centralised in the Pope then when he really has to lay down doctrine he is supposed to simply be reiterating the ancient teachings of the Church, though presumably he may make what was implicit explicit and add what naturally follows from the ancient teaching, and says when this has been done you cannot dissent with impunity. Orthodox and the Anglican Churches do the same, we may just use synods more often rather than relying on our Primates. I think that the position of the Pope is not that big a deal, if his church wants to allow it that is their business and if it claims I need to recognise his 'full' authority then I will simply ignore it.
Whether one says the ancient doctrine is infallibly True and we are just laying it before you as a Council or Synod or a Bishop or the Pope is speaking infallibly, but in doing that he is just expounding the ancient doctrine of Christ and the Apostles, seems to be a matter of not that great a difference. One may of course say this is not how it has always worked in practice, because the Pope has added new doctrines, but that is a different issue.
FatherGiryus; I would disagree there are not kinds of knowledge above deductive reasoning which are certain, like what C.S Lewis calls Intellect(following Boethius.) and of course Imagination was it was once understood. To ignore these would be to ignore a big part of Christian philosophy and mystical thought and to fall into the modern error of viewing everything as more or less uncertain and relying on endless discursive thought. But yes, I'd agree that the Pope is not using this kind of knowledge necessarily, even when he speaks 'ex cathedra'. I do not think that certain knowledge and free will are necessarily in conflict.