Things like contraception etc must be dealt with slowly. I would require all Priests to teach against it. God forbid that anyone keeps continuing in grave sɛҳuąƖ sin, but even if a Catholic sins during the week, confesses his or her sin, and then goes to Holy Mass and Holy Communion with the resolve to change, he or she is still a Catholic and can do so. A dogmatic anathema against contraception may follow later, once Catholics have, by frequenting the Sacraments, praying the Rosary etc, been led away from sin. Saints say you cannot keep continuing praying the Rosary and persisting in grave sin. You will give up one or the other.

You will always have people who have decided that they are going to live in mortal sin for at least a portion of their lives.  They gamble "I'll take the chance I won't die anytime soon, then when I'm done [doing whatever it is they feel like they have to do, or see themselves as too weak to give up], then I'll make it right with God".  That's a huge problem, but that's not the problem most so-called Catholics in our time have.  Their problem is far worse.  They actually assert that what they are doing is not wrong, that they know more than the Church knows, that what "society" or "modern times" have to say about the matter is more important than what the Church teaches. 

There are two things going on here that cloud their judgment --- money/finances/convenience/desire for an easy life, and that fact that this sin involves sex.  With regard to the latter, "the heart wants what it wants", and other things want what they want as well.  It's no more complicated than that.  (I doubt that many have thought far enough ahead, to say "if I adhere to this teaching, I may never be able to get married, because I won't be able to find a spouse who will go along with it".  People generally don't think that far ahead anymore, if they ever did.)

If they were just willing to say "I know this is wrong, I know this is a mortal sin, but I don't love God enough to avoid it, I don't trust God enough to try to live by it, we can't take a chance on that extra child, I can't lose my spouse, and besides, my gonads can't do without sex" (the latter would be far more true of males than females), then that would be bad enough.  They certainly don't cease to be Catholics, they have just made the decision to be Catholics who are willing to live in mortal sin for a time.  But to say "the Church is wrong" or "this doesn't bother my conscience", well, that's ten times worse.  There's no coming back from that, because not only do you have the sɛҳuąƖ sin itself, but you've also introduced an element of pride, fueled by a world that doesn't see anything wrong with it.

Pius XII in Humani Generis reluctantly accepted the Evolution could be possible, albeit in a purposeful, theistic way. Defining exactly how God created the world would be a hard matter.

How do you know he was reluctant and did not believe in it himself? But anyway stating the beginning of Genesis is true would be the most important thing for a traditional Pope to do. Strike at the heart of the beast. The heart of the beast today is evolution.

How do you know he was reluctant and did not believe in it himself? But anyway stating the beginning of Genesis is true would be the most important thing for a traditional Pope to do. Strike at the heart of the beast. The heart of the beast today is evolution.

Yes, that's right up there.  Probably the first victim of Modernism was the historicity and inerrancy of Sacred Scripture.

How do you know he was reluctant and did not believe in it himself? But anyway stating the beginning of Genesis is true would be the most important thing for a traditional Pope to do. Strike at the heart of the beast. The heart of the beast today is evolution.

We don't *know*, but there isn't any evidence that I'm aware of that he believed it.  He doesn't say he believed it in HG.

//36. For these reasons the Teaching Authority of the Church does not forbid that, in conformity with the present state of human sciences and sacred theology, research and discussions, on the part of men experienced in both fields, take place with regard to the doctrine of evolution, in as far as it inquires into the origin of the human body as coming from pre-existent and living matter - for the Catholic faith obliges us to hold that souls are immediately created by God. However, this must be done in such a way that the reasons for both opinions, that is, those favorable and those unfavorable to evolution, be weighed and judged with the necessary seriousness, moderation and measure, and provided that all are prepared to submit to the judgment of the Church, to whom Christ has given the mission of interpreting authentically the Sacred Scriptures and of defending the dogmas of faith.[11] Some however, rashly transgress this liberty of discussion, when they act as if the origin of the human body from pre-existing and living matter were already completely certain and proved by the facts which have been discovered up to now and by reasoning on those facts, and as if there were nothing in the sources of divine revelation which demands the greatest moderation and caution in this question.
//

Perhaps this is imprudent, but I don't see anything here that would suggest that he believed it.

We don't *know*, but there isn't any evidence that I'm aware of that he believed it.  He doesn't say he believed it in HG.

Perhaps this is imprudent, but I don't see anything here that would suggest that he believed it.

It is not in that docuмent. I don't know the exact belief he held because I have never read where he explained it in every detail. But he gave a speech to the pontifical academy of the sciences where he went on and on about the universe and the earth being billions of years old and how the big bang was like some sort of sign of God's glory. He did not go into detail on what else he exactly believed but he clearly did not believe the earth was a few thousand years old and that it was created in six days and God rested on the seventh. So the most likely thing in my mind was that he believed in theistic evolution, though it is possible that he believed in some hybrid theory.

http://inters.org/pius-xii-speech-1952-proofs-god

This might be the speech, but I did not just now read it in full. I previously read it on another website.