In my experience with textbooks, as well as being a TA for a bit, and even editing the practice questions in a couple of accounting text books for the author, I can fairly confidently say that the only thing logical about most textbooks is they start at chapter one and progress in ascending order. I've run into very few that actually build on the material in an order that makes sense.
Hell, I've even run into things like drum lesson books that don't follow a logical order as far as I'm concerned after years of teaching the instrument. I'm not going to say every teacher out there is going to use a better ordering, but there's usually at least some attempt to streamline things behind the decisions they make. Whether they succeed or fail is up for interpretation.