Why an 18 mm spine on a 7 mm book?
I’m surprised that no one else has taken up this subject. My most recent book is 232 pages and I have ordered it three different times. The last copy I received had a spine at least 1/8" wider than the pages themselves. This looks really odd to me. I’m guessing that these new bindings come in incremental sizes and they don’t always match well with the number of pages in the book.
Another difference I noticed was that the newest binding is more of a “lay-flat” binding, which changed how my page layouts and two-page spreads looked because more of the page in the gutter is showing. I try to overlap my two-page spreads, and I suppose now I have to reconsider that.