I will not go into the subjective point of view of individual laity whom you termed the "SSPX couple" (note - there is no such thing) but will only argue what can be objectively known.
Between 1970 and 1975, the priests of the Society of St. Pius X who had to celebrate a wedding ordinarily asked for and received the necessary delegation from the local pastor. From 1975 on, after the alleged “suppression” of the Society of St. Pius X, this delegation was usually denied the priests of the Society of St. Pius X (except by a few priest friends) under the false pretense that their status in the Church was irregular.
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Nevertheless, as its name indicates, the “extraordinary form” is outside of the ordinary; it can not become ordinary. It can exist only in the case where the “ordinary form” is not possible. Canon 1094, which deals with the “ordinary form”, is an “absolute” canon, which begins quite clearly: “Only those marriages are valid....” Canon 1098, about the “extraordinary form”, is only a “conditional” canon, which starts: “If...cannot,” and includes still more restrictions, such as “provided it is prudently foreseen....” The absolute and unconditional norm of marriage is therefore the “ordinary form”, whereas the “extraordinary form” is only exceptional, relative, and occasional.
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The fourth objection insists that agreeing to make use of Cardinal Müller’s Letter would ipso facto be tantamount to putting marriages according to the traditional rite into the hands of the bishops and of the Roman Curia (fierce enemies of Tradition), since these marriages would henceforth depend on the permission that they would grant...or not. This objection would be pertinent only if the Society of St. Pius X absolutely and definitively renounced the usage of the “extraordinary form”. But there are no plans whatsoever to do that. The grave state of necessity created by the crisis in the Church remains more valid than ever, and without any possible doubt it authorizes recourse, if necessary, to the “extraordinary form”. What Cardinal Müller’s letter accomplishes therefore is not a restriction of the possibilities, but rather the addition of the possibility of the “ordinary form”. And since in some cases the use of this “ordinary form” will prove to be difficult or impossible, recourse to the “extraordinary form” will remain perfectly justified. The bishops therefore will not be able to “blackmail” the Society of St. Pius X with regard to its marriages, inasmuch as an unjustified refusal of a delegation, in addition to other objective circuмstances, would altogether authorize the use of the “extraordinary form”, as has been so until now.
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The seventh objection assumes that agreeing to marry according to the “ordinary form” while requesting delegation would be a failure to profess the Faith publicly and to criticize the errors of Vatican II. In effect, the state of separation, contradiction, and conflict between Tradition and the “conciliar” Church, manifested by the canonical sanctions and the refusal of the official authorities of the Church to grant to the Society of St. Pius X what would be just and normal (for example jurisdiction, delegation for marriages, etc.), is like a “catechism in pictures” of the crisis in the Church. Upright souls who are seeking the truth, upon observing that the Society of St. Pius X is persecuted while adhering to what the Catholic Church has always taught and done, are led to think correctly that the official authorities of the Church are in error. By marrying according to the “ordinary form” thanks to a delegation received from an “official” bishop, the Society of St. Pius X would weaken in its battle against the errors of Vatican II.
This objection confuses the reality of the radical opposition between the Catholic Faith and the errors of conciliar liberalism with certain concrete situations that may accidentally manifest it. In the 1970’s, Tradition had taken refuge in makeshift shelters; then, in most localities, they bought or built a church: is anyone going to say that the battle for the Faith grew lukewarm as a result? When a priest of the Society of St. Pius X requests the use of a shrine for a pilgrimage, is anyone going to say that the battle for the Faith is diminished if he obtains permission, as compared with a refusal to grant it? When Pope Benedict XVI acknowledges that the old rite was never abolished, is anyone going to say that the defense of the traditional liturgy by the Society of St. Pius X and the heroic resistance of Archbishop Lefebvre to preserve it are discredited as a result? And so on.
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