“Does Catholic Doctrine Change?”
by Fr. Francis J. Connell, C.SS.R.
This is as far as anyone needs to read - Fr. Connell was another one of the respected 20th century theologians who helped pave the way for conciliar religion.
Some people like you are just too smart for your own good. At some point those of your ilk will figure out that they're the only Catholics around -- and the only Catholics that have ever lived.
Maybe Fr. Connell, who was a REAL and extremely well-educated theologian, and recognized as such, ALSO knew a little bit about Sacred Theology...  

I think a lot has to do with woefully inadequate knowledge about Catholicism. A lot of traditionalists are such simply because they read SSPX propaganda. Some people back in Pius X day thought that lowering the age of First Communion was very imprudent and would introduce much irreverence. Can you imagine, many of today's traditionalists might have denounced him as a modernist or modernizer!
All of us are looking at Church history from the convenient perspective of the late 20th / early 21st century. We know St. Pius X was a saint, but the people in the 1900s and 1910s didn't know that. Likewise, when Benedict XV phased out the Sodalitium Pianum, he didn't know that the consequences would ultimately be disastrous. He just thought it was more prudent to phase it out. Turns out he was wrong. But back in the 1910s and 1920s that wasn't apparent.
Remember n. 24 from Pope Benedict's "Ad Apostolorum": "It is, moreover, Our will that Catholics should abstain from certain appellations which have recently been brought into use to distinguish one group of Catholics from another. They are to be avoided not only as "profane novelties of words," out of harmony with both truth and justice, but also because they give rise to great trouble and confusion among Catholics. Such is the nature of Catholicism that it does not admit of more or less, but must be held as a whole or as a whole rejected: "This is the Catholic faith, which unless a man believe faithfully and firmly; he cannot be saved" (Athanas. Creed). There is no need of adding any qualifying terms to the profession of Catholicism: it is quite enough for each one to proclaim "Christian is my name and Catholic my surname," only let him endeavour to be in reality what he calls himself."
That was said to quell the controversy about "integrist Catholics" vs. "modernist Catholics".