That is precisely the pragmatic kind of thinking that has prevailed in the Church since Humanae Vitae, and in the pro-life movement since Roe vs. Wade. How many times have you heard, "If we can save just one life..."?
But evil may never be done that good can come of it. We may never abandon our principles, not even to save a life. We can act to save one life by doing something inherently good and charitable, but never by admitting that it's okay to kill some other babies. Presenting muddled justifications for the Church's ban on contraception may not rise to the level of "evil," but like the pragmatic approaches to the pro-life movement, it represents an abandonment of principle.
The most authoritative document on marriage ever issued by the Catholic Church is the encyclical "Casti Connubii" by Pope Pius XI. He taught definitively that the reason why contraception is wrong is because it violates the primary purpose of marriage which is the procreation and education of children. Where do you see that principle enunciated in any of the several articles that were posted to start this thread? Nowhere.
So the reality is that essential Catholic principles have been abandoned. This can never lead to good, only to evil.