A general note to the whole thread:
In his work
Catholic Apologetics Today: Answers to Modern Critics and elsewhere, the late Fr. William makes the following threefold distinction, which I believe is very helpful to discussion like these: “ First of all, we must carefully distinguish and keep separate three areas: (1) The
teachings of the Church (doctrine); (2) the
rules or commands of the Church (legislation); (3) the question of
how prudently the Church has acted in a given case.” (Appendix 1,
Library - Most Theological Library | Catholic Culture)
As catholics, obviously we must always believe and uphold 1), and we must submit to 2). This is because Divine protection is promised to 1), and a divine mandate is given to the Apostles and their successors to do 2).*
In area 3), however, there is no divine guarantee, protection, or promise; it is not guaranteed that the Church will always act in the most prudent manner. For this reason, there can be legitimate, respectful disagreement among Catholics.
For example, Catholics may disagree that it was the most prudent to define papal infallibility when it was. Indeed, many good Catholics did, notably St. John Henry Newman.
Similarly, Catholics may disagree on whether Vatican II (and the post-Vatican II approach of Popes, for the most part)’s approach of positively teaching doctrine rather than condemning negative propositions is the most prudent at this time. Or, Catholics may disagree that the reforms of the Liturgy were the best idea. In doing this, we obviously are not setting ourselves against the Church in an area where we are not permitted to do so.
Finally, it should go without saying that if we are to disagree on a given aspect of 3), the disagreement has to be respectful, and we be careful not to deny 1) or withdraw submission to 2).
*It should be noted that, in her universal disciplinary laws, the church enjoys an indirect and negative infallibility, meaning that it can enact nothing contrary to Divine Law or forbid anything that divine laws exacts. It is possible for these laws to be in accord with divine law but not the most prudent decisions in a given situation.