science

You keep using that word. I do not think it means what you think it means. Tautology doesn't mean obvious or predictable, and you're basing your argument on faulty premises. The study measured how many politically-aligned couples separated in a 1-year period compared to how many politically-opposed couples did so.

people separate because they have irreconcilable differences

Yes, sometimes that's a reason people separate.

opposing political views is an irreconcilable difference

It's sometimes irreconcilable, and sometimes not. Couples with opposing political views are more likely (but not guaranteed) to separate than couples who agree.

the conclusion of the research is that couples with irreconcilable differences are more likely to suffer from the problems associated with irreconcilable differences

Nowhere in the study do they declare political heterogamy an irreconcilable difference, nor could they without 100 years of data. You keep referring to "the proposition" and "the research subject" and "the conclusion" and then inserting your own phrases and concepts that were literally not a part of the study. And this is all in defense of your original comment in which you cast an aspersion on the value of the study and then claimed that you didn't. You've made previous comments with the same low-effort "study finds that water is wet" so I don't believe we're both speaking in good faith here.