One of several interesting point's in Brant's work is his analysis of the headnotes that Mormon apparently provided in some parts of the book. Here is the relevant excerpt:
Several clues in Mormon's text bear evidence that he had at least created a full outline of his work before he began the task of committing it to the plates. Perhaps the most obvious evidence is the chapter headnotes which were physically written on the plates prior to the chapters they synopsize. The extant portion of the original manuscript preserves synoptic headnotes for Helaman and 3 Nephi, confirming that the 1830 edition's headnotes were part of the translation and were not added in the preparation of the Printer's manuscript when Joseph or Oliver could have created them from their reading of the original. As a representation of information from the plates, they indicate that Mormon wrote them prior to the chapters and therefore had to know the contents of the coming chapter before he began to write it.
The majority of the headnotes are at the beginning of named books. In the small plates, they appear only at the beginning of 1 Nephi, 2 Nephi and Jacob. In Mormon's editing of the large plates, they appear at the beginning of every book but Mosiah. A headnote's absence there is understandable because the lost 116 pages apparently included at least the first chapter of Mosiah. I feel fairly safe in concluding that Mosiah would have had such a headnote, given Mormon's consistency in the remainder of the books he edited.
In contrast, there are no headnotes for Mormon, Ether, or Moroni--three books he did not edit. Mormon's consistency in adding these introductory headnotes to the books that he is editing suggests (and is corroborated by other types of internal evidence) that he had some clear plan of what he was going to include in each book he edited. When Mormon switches to his own record, it is no longer a part of the planned text and therefore does not have the synopsis in a headnote.
Although there is evidence for an outline, there is also evidence that Mormon did not simply copy a previously written text onto the plates. While he certainly copied the various sermons from his source material, in his own text he allowed himself to interact with the information he was writing. We often see Mormon divert from his outline on a tangent occasioned by thinking about the material he was writing. The evidence both for the asides and for the outline from which they diverged comes in the way he returns to his task. In order to reset his narrative to the outline, Mormon repeated at least the idea, and often much of the language, of the last part of the outline before the departure.
I had noticed this process in the text well before I had a name to identify it, which (thanks to David Bokovoy) I now have. Bokovoy relates the technique as it is known from the Old Testament: "Repetitive resumption refers to an editor's return to an original narrative following a deliberate interlude. Old Testament writers accomplished this by repeating a key word or phrase that immediately preceded the textual interruption."