I said very early in this thread that, on this topic, the tendency is to suggest that a marriage is a more superior relationship.
I've got no way of knowing whether my relationship is "better" than yours and I'd never presume to say anything of the kind. Nor would anyone unless they were a complete idiot.
But I do say mine has a legal commitment to it that yours hasn't. Doesn't mean we're more in love, have better sex, or that I'm owned. But it does mean we've got a legal contracted commitment in place, with certain protections, that you haven't. That's all.
That being married somehow demonstrates a level of commitment lacking in non married couples.
Because legally it DOES. The fact that you don't recognise this is why I really don't believe you're a lawyer. You don't think or talk or reason like one.
It says nothing about emotional commitment, for sure, but it's never claimed to in the legal part of it (as a poster showed above about the required lines you have to say - nothing about love or emotion at all). Marriage for love is a fairly recent concept; it always used to be about security and alliance. It wasn't long ago that kings in waiting had to abdicate if they wanted to marry a divorced woman, for love.
I don't say my relationship is in any way emotionally better than yours, but I DO say it is more legally committed, for the simple reason that it IS. We have a contract in place and you haven't.
You want legal benefits like IHT exemption, which are fuck all to do with love, you need to make the legal contract.