Settle an argument — whether Euron's horn does what he says it does

I have been on both ends of what follows. Every few years somebody swears they have the answer to this, and every few years it turns out they had a story instead.

The question, put plainly: whether Euron's horn does what he says it does. I have changed my mind on this twice, which is more than most will admit to.

There is a version of this where the truth is dull — a bad decision, a bad winter, nobody's grand design — and I have never once heard anybody argue for it.

Do it properly the first time. I did not.