I believe you are erroneous when you state "Ecumenical councils don't have to make definitive statements to be infallible". The statement which you introduce from Cardinal Ratzinger simply states that divine assistance is given. The very fact that he distinguishes this assistance from cases of an infallible definition shows that he doesn't consider this assistance to make the non-definitive statement infallible.Divine assistance can never be fallible; on the contrary, it is Truth Itself. It is the long-standing belief of the Church that its infallibility is derived from the assistance of the Holy Spirit Who is within it. The belief that the Holy Spirit assists the apostles assembled in a council in union with Peter was there from the beginning. At the council of Jerusalem (a pastoral council), it is apparent that the apostles believed their decisions were guaranteed by the Holy Spirit:
--gbcdoj
For it hath seemed good to the Holy Ghost and to us to lay no further burden upon you than these necessary things: That you abstain from things sacrificed to idols and from blood and from things strangled and from fornication: from which things keeping yourselves, you shall do well. Fare ye well.Most of the individual truths that compose the infallibly taught deposit of faith have never been the subject of a statement made "ex cathedra" by a Pope or the subject of a canonical declaration. The distinction made by Cardinal Ratzinger is between the infallibility that is accompanied by a definitive statement and the infallibility that isn't. He is not saying divine assistance is fallible in one case and infallible in the other!
--Acts 15:28-29
An excerpt from your Catholic Encyclopedia citation:
Arguments contained in conciliar definitions are proposed by the supreme teaching authority in the Church, they concern faith and morals, and they bind the Universal Church; yet they are not definitions, because they lack this fourth condition -- they are not definitively proposed for the assent of the whole Church.As you can see, I emphasized different phrases than you did. The citation is not saying that because a conciliar teaching is not, strictly speaking, a "definition" it is not "proposed by the supreme teaching authority of the Church," and does not "bind the Universal Church." On the contrary, the citation makes clear that non definitive conciliar teachings are still promulgated by the "supreme teaching authority of the Church" and still "bind the Universal Church."
--Catholic Encyclopedia
Definitive statements are not the only teachings of the Church that are binding. Non definitive statements "bind the Universal Church," and, because they are non definitive, it is of course true that "they are not definitively proposed for the assent of the whole Church." This does not, as the quote make clear, lessen their authority as they are "proposed by the supreme teaching authority of the Church" and it does not lessen their binding nature as "they bind the Universal Church."
Another excerpt:
It should be noted that not everything contained in a definition is infallibly defined. Thus, arguments from Scripture, tradition, or theological reason, do not come under the exercise of definitive authority. Incidental statements, called obiter dicta, are also examples of non-definitive utterances. Only the doctrine itself, to which those arguments lead and which these obiter dicta illustrate, is to be considered as infallibly defined.This is saying that "not everything contained" in a definitive statement is infallible, not that only definitive statements are infallible. The Council of Jerusalem, which was obviously disciplinary rather than dogmatic, and therefore made no "definitive" statements, still explicitly claimed its decisions had the approval of the Holy Spirit. All officially assembled ecumenical councils can and do make this claim. That is why Ratzinger says you have to buy into Trent, Vatican I and Vatican II and that it is nonsensical to reject one council and accept others. Catholics believe the Holy Spirit assists and guarantees ecumenical councils.
--Catholic Encyclopedia