Here's what UUS 10 really says:
10. In the present situation of the lack of unity among Christians and of the confident quest for full communion, the Catholic faithful are conscious of being deeply challenged by the Lord of the Church. The Second Vatican Council strengthened their commitment with a clear ecclesiological vision, open to all the ecclesial values present among other Christians. The Catholic faithful face the ecumenical question in a spirit of faith.The Council states that the Church of Christ "subsists in the Catholic Church, which is governed by the Successor of Peter and by the Bishops in communion with him", and at the same time acknowledges that "many elements of sanctification and of truth can be found outside her visible structure. These elements, however, as gifts properly belonging to the Church of Christ, possess an inner dynamism towards Catholic unity".11
"It follows that these separated Churches and Communities, though we believe that they suffer from defects, have by no means been deprived of significance and value in the mystery of salvation. For the Spirit of Christ has not refrained from using them as means of salvation which derive their efficacy from the very fullness of grace and truth entrusted to the Catholic Church".12
You are quoting from a bad text, which drops most of the first paragraph of UUS 10.
"It follows that these separated Churches and Communities, though we believe that they suffer from defects, have by no means been deprived of significance and value in the mystery of salvation. For the Spirit of Christ has not refrained from using them as means of salvation which derive their efficacy from the very fullness of grace and truth entrusted to the Catholic Church".12
I'm sorry to interrupt here, but that just jumped out at me. What does that MEAN? Do you really think that this is clear? I'm not the most intelligent person in the world, but I'm not stupid. That is gobblety gook. Do you really believe that clarifies Traditional Catholic doctrine?
"these separated Churches and Communities,"(not part of the Catholic Church, in that they are [separated] from Her,)[snip]" Christ has not refrained from using them as means of salvation".
Other "churches" are a means of salvation? Although they are not Catholic, they still can "derive efficacy from the Catholic Church". Heck, why bother being Catholic.
Boy it's a good thing the pope wasn't a car salesman. I can just imagine the sales pitch:
I have the best, most equipped cars, but the other car dealerships also have cars that will get you where you need to go to, (most of them for far less cost and maintenance, too by the way).