I dunno guys… :-/
All the explanations I’ve read about why it’s wrong to wear a condom, say that the intention (if just) is not the problem, because it is the same intention as using NFP - to avoid pregnancy. The problem is simply the fact that you are wearing something that does not allow sperm into the body. That is why it is wrong for a married couple to wear them even if the woman has a hysterectomy and can’t get pregnancy anyway. Because it is not the intent that is wrong, it is the fact that sex is being changed by taking sperm out of the equation.
So let’s suppose the couple has just reason to avoid pregnancy. The intent is the same, whether they use NFP, Condoms, or perforated condoms. The intent is not the problem.
The moral object comes next.
Is periodic abstinence, in and of itself, a sinful act? No.
Is using a condom during intercourse, in and of itself, a sinful act? The Church teaches, yes.
Is using a perforated condom during intercourse, in and of itself, a sinful act? Clearly, no, otherwise it wouldn’t be permissible to use them for intercourse for ANY reason.
So when you put a licit intent together with a licit moral object, I don’t see how it can still be a sin.