What is missing in this commentary (totally understandable in the context of the French elections) is to stand back and note how the traditionalist schism (Lefebvre and SSPX) was far more political than theological. They manipulated the Tridentine Latin Mass as a respectable "flag" to rally far right wind sympathisers.

So, for example, want to find the most anti-Semitic literature available in Europe? Go to Mass in the SSPX church in Paris, and it's all there. 

Something that helps explain the "Catholic" support for the National Front.