> But at least it gets the core design stronger by operating on higher level goal/paradigm constraint (the purpose of procreation)
That's actually not how it works; the intricacies of the dual procreative and unitive function model in the theology under Humanae Vitae is no less complex than that of the consent-based system, but it's just based on a moral system with a larger number of specialized axioms; the consent-based system is based on a simpler set of axioms, because it doesn't need a specific set of axioms for sex; the principle of consent underlying the consent-based system of sexual morality is the same one underlying all of the liberal enlightenment political/social/economic ideology.
That's actually not how it works; the intricacies of the dual procreative and unitive function model in the theology under Humanae Vitae is no less complex than that of the consent-based system, but it's just based on a moral system with a larger number of specialized axioms; the consent-based system is based on a simpler set of axioms, because it doesn't need a specific set of axioms for sex; the principle of consent underlying the consent-based system of sexual morality is the same one underlying all of the liberal enlightenment political/social/economic ideology.