I took part in a pretty discouraging discussion several years ago with maybe a dozen alumnae from my SSPX-affiliated school. I was nearly alone of those who took part who knew the “old” rules: 1) with the guidance of the priest 2) for *grave* reasons, aka life or death and 3) for no more than 2 years. 
 
Nearly all of the girls who took part, especially the younger ones,  had been taught by SSPX priests in a variety of parishes that as long as the spouses agree, NFP could be used for reasons of health, spacing and finances. But this was quite vague. Let’s just say the *grave reason* had been ratcheted all the way down to serious or even moderate inconvenience. Some were even encouraged to space 2-3 years just because. They said they were encouraged not to have them too closely so they could have the time and finances to dedicate to each child. (Is this not the definition of worldly “prudence” and worldly reasons for contraception??) But they did not recognize it as such. And they’ve been taught all their lives to listen to SSPX priests. So that’s what they are doing and see absolutely nothing wrong with it. They even seemed happy to accept more relaxed guidelines as being more enlightened. One family said they’ve had lively conversations between the parents, who had been taught the old rules, and themselves who were now marrying and being taught much more relaxed guidelines. There was a consensus of a shift from older priests and generations to younger priests and generations. Not only younger priests, but European priests as well, seem to be teaching the more relaxed ways. Americans tend to be more Puritanistic therefore too rigid with the rules was the rationalization.
 
I can’t even tell you some of the reasons that some of the girls gave as examples because I couldn’t bear the ridicule they would get, even if it’s anonymous. They’ve been led to believe it’s all good. And even noble! To abstain for the good of their children who are already living! Such a sacrifice! After all, having too many children puts their children’s souls at risk if they can’t be raised properly.
 
They make it sound good, but when you brush away the surface arguments, the principle at the root is rotten. And deeply materialistic. The idea of relying Divine Providence was not outright dismissed but was seen as borderline dangerous because it’s not prudent. That Providence stuff gets overdone by people who are too zealous. Those people ruin their children. So we have to do both, rely on Providence but also be prudent (as if they are at odds!) And we live in a different time, the demands of society etc.. etc… All the rationalizations were front and center. I wish I were exaggerating. It was a little heartbreaking.
 
Before this discussion, I had had another discussion with someone from St Mary’s who had been told they could practice NFP for reasons of their own as long as she and her husband were in agreement. There was no need to consult a priest. I clarified with her because I thought maybe I misheard her. Then I distinctly remember thinking maybe she misunderstood the priest. I thought that to myself as a way of giving her the benefit of the doubt since I knew their reason for NFP at the time and it was far from life or death. It was about 3 years later that this discussion with the alumnae opened my eyes and I realized this is systemic and the first lady had not been mistaken at all. Her priest had really taught her that.
 
The NFP rot is there. We can’t see it fully because who goes around discussing this topic with random parishioners to ask what their priests are telling them?! But the few times I have had the discussion, I’ve seen it. And it seems fully sanctioned. The only reason I am able to see it is because I have known people who were NO and who spaced using NFP for all those same reasons. When they became traditional many years ago, NFP (as a rule) went out the window and so did all the thinly-veiled worldly reasons for it. They were encouraged to fling themselves entirely upon the mercy of Divine Providence. So when I see these girls now taking a step back to the NO attitudes, I fully recognize it for what it is. All the Catholic spin and vocabulary in the world doesn’t change the underlying idea: It’s much classier not to have too many children.  
 
Few people are being taught to be fools for Christ anymore. If we are weaker than previous generations it is only because we want to be. Can you imagine the large families of old having a quarter of the comfort, convenience, medical care and goods that we have? How happy they would be? But somehow we use it all as an excuse to have smaller families. It’s amazing.