This activity should, in our opinion, be the very first thinking/writing you do when starting your dissertation. By following these steps you will build a solid logic and a firm foundation.
Writers of all kinds must write to the guidelines of those who will publish their work. Those working on their dissertation proposal or final as part of their doctoral education are under the same constraints. As a writer, I find the guidelines of the journals etc. for whom I write to be restrictive, and I know that my doctoral students feel the same. We both just have to get over it, and realize that if we want to pass these outside criteria we must do exactly what is required.