This wasn't as boring as it sounds like it would be, but I certainly didn't love it. I really got bogged down in the middle section that was almost entirely about Europe and fish, but the first section was pretty good and the end was better than the middle.
But it did feel as if the author was scraping to find mentions of salt besides the big ones. Of course salt is important, and so are lots of other things that aren't very noticeable, like water. Since this only focused on salt, I didn't feel like I got a sense of its commercial importance in comparison to other products.
It was also really Eurocentric. There was a fair bit about China, but that hardly balances Europe. And the only part about India was in relation to British colonialism. And there were lots and lots of recipes. Not recipes you'd use, but medieval and colonial recipes. That's interesting, but there were a lot.
So in all, I thought it was too long. There's a children's book by the same author that's probably the right length.