Pope Pius IX, Vatican Council, Session 3, Chapter 4, #14, ex cathedra: "Hence, too, that meaning of the sacred dogmas is ever to be maintained which has once been declared by Holy Mother Church, and there must never be any abandonment of this sense under the pretext or in the name of a more profound understanding."
Pope Pius IX, Vatican Council, Session 3, Canon 4, ex cathedra: "If anyone says that it is possible that at some time, given the advancement of knowledge, a sense may be assigned to the dogmas propounded by the church which is different from that which the church has understood and understands: let him be anathema."
So, Vatican II could not "change" Catholic teaching and nowhere did the Council ever claim to be doing that. So, what to make of those "rejected" schemas? Here are the possibilities:
1) Vatican II was trying to be pastoral. This was the official position of the Council. "It isn't what you say but how you say it," was probably the mindset of many (we hope, most) of the Church fathers. So, while they may have found the traditional and original schemas to be completely orthodox and valid expressions of the Catholic faith, they may have wanted to "tone down" the language of those schemas while at the same time affirming everything that those schemas were professing.
2) Vatican II taught poorly. In trying to be nice, the Council opened-up a Pandora's box of disillusionment and confussion.
3) Vatican II taught error. While not explicitly denying the Catholic faith, the Council promulgated teachings that are contrary to it.
4) Vatican II taught heresy. One or more of the Council's teachings constitute a denial of the Catholic faith.
The burden of proof is, clearly, on those individuals who would advance Option #3 and/or #4. Since Option 1 is the official position of the Council, that is the one that we ought to affirm, while retaining absolute fidelity to the Ordinary and Supreme Magisterium of the Church. We deny nothing which came "before" Vatican II.
In any case, the following point must be observed:
The Ordinary and Universal Magisterium of the Holy Roman Catholic & Apostolic Church is infallible, which means that the original schemas at Vatican II, to the extent that they describe the Ordinary Magisterium of the Church, are also infallible. It does not matter if Vatican II "approved" them or not. Their approval comes from Heaven, the ultimate source being the immutable One and Triune God.
Saint Vincent of Lérins (died 445) affirmed the infallible Ordinary Magisterium of the Church:
Moreover, in the Catholic Church itself, all possible care must be taken, that we hold that faith which has been believed everywhere, always, by all. For that is truly and in the strictest sense "Catholic," which, as the name itself and the reason of the thing declare, comprehends all universally. This rule we shall observe if we follow universality, antiquity, consent. We shall follow universality if we confess that one faith to be true, which the whole Church throughout the world confesses; antiquity, if we in no wise depart from those interpretations which it is manifest were notoriously held by our holy ancestors and fathers; consent, in like manner, if in antiquity itself we adhere to the consentient definitions and determinations of all, or at the least of almost all priests and doctors. (Vincent of Lerins, Commonitory, 6)
But, possibly, this warning was intended for the Galatians only. Be it so; then those other exhortations which follow in the same Epistle were intended for the Galatians only, such as, "If we live in the Spirit, let us also walk in the Spirit; let us not be desirous of vain glory, provoking one another, envying one another," etc.; Galatians 5:25 which alternative if it be absurd, and the injunctions were meant equally for all, then it follows, that as these injunctions which relate to morals, so those warnings which relate to faith are meant equally for all; and just as it is unlawful for all to provoke one another, or to envy one another, so, likewise, it is unlawful for all to receive any other Gospel than that which the Catholic Church preaches everywhere. (Vincent of Lerins, Commonitory, 24)
There are innumerable instances of this kind, which for brevity's sake, pass over; by all of which, however, it is manifestly and clearly shown, that it is an established law, in the case of almost all heresies, that they evermore delight in profane novelties, scorn the decisions of antiquity, and, through oppositions of science falsely so called, make shipwreck of the faith. On the other hand, it is the sure characteristic of Catholics to keep that which has been committed to their trust by the holy Fathers, to condemn profane novelties, and, in the apostle's words, once and again repeated, to anathematize every one who preaches any other doctrine than that which has been received. (Vincent of Lerins, Commonitory, 63)Saint Thomas also affirmed the above teaching:
Our Faith is identical with that of the ancients. Deny this, and you dissolve the unity of the Church. We must hold this for certain: that the faith of the people at the present day is one with the faith of the people of past centuries. Were this not true, then we would be in a different church than they and, literally, the Church would not be One. (On the Truth of the Catholic Faith, q.14, a.12)Mr. Brian Kelly, in his article Baptism of Desire: Its Origin and Abandonment in the Thought of Saint Augustine, quotes some modern Church scholars:
Father Jurgens: “If there were not a constant tradition in the Fathers that the Gospel message of ‘Unless a man be born again . . . etc.’ is to be taken absolutely, it would be easy to say that Our Savior simply did not see fit to mention the obvious exceptions of invincible ignorance and physical impossibility. But the tradition in fact is there, and it is likely enough to be so constant as to constitute revelation.” (Jurgens, The Faith of the Early Fathers, Vol. 3, pp. 14-15, footnote 31)
Next, Rev. Bernard Otten, S.J., one-time professor of both Dogmatic Theology and the History of Dogma at the University of St. Louis, Missouri, in his Manual of the History of Dogma wrote: “Baptism of water, although ordinarily necessary for salvation, may be supplied by martyrdom, and under certain conditions also by the baptism of desire. The former was universally admitted, but the latter was apparently denied by Chrysostom and Cyril of Jerusalem.” (Vol. I, pg 351) Abbot Jerome Theisen, O.S.B., in his book, The Ultimate Church and the Promise of Salvation, affirms the same of Saint Gregory Nazianzen and adds Saint Basil as being opposed to the speculation.
And, lastly, Rahner:
“. . . we have to admit . . . that the testimony of the Fathers, with regard to the possibility of salvation for someone outside the Church, is very weak. Certainly even the ancient Church knew that the grace of God can be found also outside the Church and even before Faith. But the view that such divine grace can lead man to his final salvation without leading him first into the visible Church, is something, at any rate, which met with very little approval in the ancient Church. For, with reference to the optimistic views on the salvation of catechumens as found in many of the Fathers, it must be noted that such a candidate for baptism was regarded in some sense or other as already ‘Christianus,’ and also that certain Fathers, such as Gregory Nazianzen and Gregory of Nyssa deny altogether the justifying power of love or of the desire for baptism. Hence it will be impossible to speak of a consensus dogmaticus in the early Church regarding the possibility of salvation for the non-baptized, and especially for someone who is not even a catechumen. In fact, even St. Augustine, in his last (anti-pelagian) period, no longer maintained the possibility of a baptism by desire.” (Rahner, Karl, Theological Investigations, Volume II, Man in the Church, translated by Karl H. Kruger, pp.40, 41, 57)Of course, Saint Augustine stated,
“Not one of the elect and predestined perishes, regardless of his age at death. Never be it said that a man predestined to life would be permitted to end his life without the sacrament of the Mediator. Because, of these men, Our Lord says: ‘This is the will of the Father, that I should lose nothing of what he has given me.’” (St. Augustine, Against Julian 5, 4)It may be that many of the Church fathers viewed martyrdom as being a second Baptism.