I don't know much, but the training of priests seems really important. The pre-Conciliar popes strongly advocated St. Thomas to be the teacher of all seminarians, as his principles are those that best refute the principles of Modernism. We've seen the rise of Modernism / neo-Modernism in the seminaries to a very great degree & a corresponding abandonment of St. Thomas. Now, a lot of these priests that one would like to call heretics may not be formal heretics, i.e. they may not be purposefully setting up their minds against the Church. I imagine a lot of them think that their liberal theology is just what the Church wants, because that is what they learnt in the seminaries. In other words, they may not all be malicious, just extremely poorly-formed in theology.
The theological training of priests is of the highest importance because it affects everything the priest thinks, says, and does. If a priest, for example, is given the vague impression by his theology professor that hell is empty because everybody who is nice goes to heaven, and everybody is nice, that will have a great impact on how he acts as a priest. He will see no urgent need to convert souls. He will see no urgent need to encourage piety and devotion in his flock. He himself will perhaps lose devotion or grow cold, because he doesn't realise the urgent necessity of it for salvation. He will lose, perhaps, a sense of reverence for the liturgy because he no sees how this is intimately tied to our sanctification and thus our salvation. He's a Pelagian, perhaps without knowing it.
At Vatican II, the liberals were a very organised group of dissidents. The pope allowed the liberals to have a voice. In order to turn the Church back, what will be needed is another ecuмenical Council where the traditionalists are a very organised group of dissidents, and with a sympathetic pope who would grant these traditionalists a voice. What caused the liberals to be so organised and so zealous, and the pope to be so sympathetic them, was the sense that the Modern world was full of untold promises and joys that, if the Church could only accommodate itself to the Modern world, will be bestowed upon all Catholics.* Therefore, what will cause the traditionalist counter-Revolution, is a strong sense of disillusionment with the modern world, a strong sense that separation of Church & State is NOT the ideal form of government, and that the liberal peace of tolerance of all creeds/religions is a false peace, and a return to "Catholic supremacism" (the vivid awareness that the Holy Catholic Church is alone the mystical body of Christ and the ark of salvation).
* to see this exuberant optimism for the modern world, read Pope John XXIII's first encyclical, Pacem in Terris. It has a completely different tone to the encyclicals of his predecessors. It sounds a lot like the docuмents of VII.
http://w2.vatican.va/content/john-xxiii/en/encyclicals/docuмents/hf_j-xxiii_enc_11041963_pacem.html
Here's a quote from the same pope's opening speech of VII:
"We feel we must disagree with those prophets of gloom, who are always forecasting disaster, as though the end of the world were at hand."
These "prophets of gloom" include the pre-VII popes. They were all warned against the evils and threats of the modern world. Pope John XXIII was the first to abandon this repulsion for the modern, liberal world for a warm hug. In summary, the modernist theologians and those of similar mind, got caught up in the revolutionary enthusiasm of the post-French Revolution era, with the sense that there was a bright new future for mankind just around the corner. It's practically an abandonment of the doctrine of Original Sin and the truth that, without God, man can do nothing, and that: "If the LORD does not build a house, then those who build it work in vain."