Pope Paul VI spoke of the smokes of hell entering the Church.
While I have no idea as to what he exactly meant, I would like to examine a situation of "traddies" vs. "libs" in the Church of today: we have two opposing groups that classify themselves either as "traditionalists" or "liberals".
I would like to point out that I would use neither of the above labels for myself: the only thing that matters to me is orthodoxy in the faith: that is to say: loyalty and obedience to the Magisterium.
Listening to a sermon of Archbishop Fulton Sheen on the Devil, I gathered one very important aspect: the diabolical is shown in discord. Now, consider this in regards to the Church, the Eucharistic people united as ONE Body through the sacrament of Holy Communion (1 Corinthians 10:17).
With that in mind, remember the words of the Lord asking the Father to keep us in His name that we may be one (John 17:11-12).
I believe that we can see the works of the Devil in the Church today in discord. Precisely in this "traddies" vs. "libs" mentality. They fight over the Council (Vaticanum II), the Form of the Mass of the Roman Rite (either ordinary or extraordinary), the way of receiving the Body of Christ (on the tongue or hand), etc..
What these two opposing groups do have in common is that not a small amount of them forget the obedience and loyalty they owe the Magisterium. There are those - from both groups - who deem themselves smarter or wiser than the Pope and the College of Cardinals together. The hierarchy based on loyalty and obedience breaks down (see: Hebrews 13:17). With that, unity is disturbed at best or totally destroyed at worst. You will have certain sectarian groups claiming to be "true Catholics" but explicitly disobey the visible head of the Catholic Church (e.g.: the Society of Saint Pius X, a.k.a. SSPX).
One hears excuses such as "I am only bound to obey dogmas" from both sides, however the Church teaches that not only dogmas have to be obeyed:
One side views everything from Vaticanum II onwards as being "unCatholic" or "too protestantized" while the other views the reforms as "not being enough" and "still too conservative". Then you have the ones who start acting autonomously - as though they were not any longer members of a visible Church with a system of hierarchy.
In the end, you have the same result: both groups are hurting the visible unity that God wants from the Church. One is not truly united with the Catholic Church when one refuses to obey and remain loyal to the Magisterium.
The opponent is indeed very smart and cunning: he has a method for each type: for the "traddies" and "libs". Both deal with disobedience and arrogance: thinking that one is better qualified to make theological judgements on Conciliar decisions and decrees from Rome than the Church's teaching Body. Oddly enough, disobedience and arrogance are what caused the fall of Satan.
Humility, loyalty and obedience would help us overcome the current discord. It does not matter how "nice" certain things sound to us: if these things are not in line with the Church's position, then they have to be disregarded.
You are commanded to "believe not every spirit, but try the spirits if they be of God: because many false prophets are gone out into the world" (1 John 4:1).
"We are of God. He that knoweth God, heareth us. He that is not of God, heareth us not. By this we know the spirit of truth, and the spirit of error" (1 John 4:6).
If one promotes an idea that would lead to disobedience (even if it is claimed to be "partial" or "temporary" only), then we know that it will lead to discord...
..then we know that it is smoke from the darkest pits of hell!