Mawarrage! Mawarrage is what brwings us twogether twoday. Because lwuv, twue lwuv ....
(couldn't resist

sorry

)
I'd be curious to see what sort of unexpected consequences something like this would have. Could be good, could be bad. It would definitely be interesting.
Consenquences? What I can see is that there'd be a lot of half-brothers and half sisters running around and think in the long term what that would do to the gene pool.
Also people wouldn't marry for love and what's the point of that? Without love and sustaining love our society, I earnestly believe would crumble and degenerate eventually to nothing. All the (bad) stuff we talk about in the Study about spousal murders, and rapes and molestations would blossom to horrific proportions. Why? Because without love without the concept of loving for a lifetime children growing up in this "bubble", which is a concept that is
felt as well as thought of, would grow up not having the love within them to stop doing these horrific crimes. They wouldn't care.
That, Miss Tina Turner, is what's love got to do with it.
You marry someone
because you love someone and can't imagine loving anyone else (that way or that deeply). You WANT to stay with them forever and a day.
People who divorce after a few years of marriage didn't truly see the depths of their affections for their (former) S/O because they were blinded by the moment... and probably by the itch in their crotches. Best way to know is if you're willing to wait... and you do.
Having a contractual marriage just eliminates that (deep-true-love) from the equation. Besides they have that here in the states anyway... it's called Common-law marriage. It's beneficial to the point of helping one another get out of debt faster and getting certian tax breaks to achieve that.
It also helps reduce (not eliminate) the chances of STD's because you're with ONE partner... provided each stays within the confines of the "agreement".
Marriage does that sure, but call it a "life-time warranty"... yet I'll concede that unfortunately the warranty isn't exactly a guarantee... but it's awfully close and does work in many cases that I know. ... but the cases that I know it DIDN'T work outnumber the ones that did work.
Sigh.