I have recently had to write and turn in my dissertation. To do this, I had to adhere, at least somewhat, to the stylistic whims of Kate Turabian. Which has been a painful process.
Who is Kate Turabian? She is a former bureaucratic pencil-pusher who leveraged her tiny bit of control over dissertation layout into a world-wide empire enforcing her anal-retentiveness about margin widths and heading formats through a book she wrote explaining how she liked things to be. Because she had to approve dissertations at the University of Chicago, students had to do whatever she said to graduate. She herself never even finished college, and never wrote a dissertation. She certainly never wrote a college term paper using her made-up style. She just made others follow it. Margins on the left should be 1.25" while the right 1"? Appendix titles are only 1" from the top margin, but chapters 2"? It doesn't matter if it makes sense, you just have to do it, or you can't get your PhD.
And that's all her wikipedia page should say about her.