Text: Mormon begins the story with a synopsis. His source may have been either the “official” royal history kept by Mosiah’s historian or the record kept by the party of sixteen. It will soon become apparent, however, that the latter is correct. Either Mormon was using it directly or it was later copied into the “official” record. Given the varied nature of the other sources Mormon uses (letters, missionary accounts, and secondary records such as that behind 3 Nephi) it would be most logical that these various sources had been copied into the plates of Nephi rather than being stored as separate records.
Literature: There is a slight possibility that this verse camouflages a Mesoamerican literary style. Several Mesoamerican languages allow a single “word” to incorporate pronouns, verbs, and direct and indirect objects. This linguistic ability to contain what we would consider short sentences in a single word or couple of words led to a structural parallelism that was not built on twos, which is common in English (repetition of an element so that there are two representations of it) but rather on a set of three in which each element was a different adjectival or adverbial description of the main subject.
For example, Ammon is characterized by three descriptions: he is a “strong and mighty man,” “a descendent of Zarahemla,” and “also their leader.” If we assume that Joseph Smith is translating meaning more than words (as evidence throughout this commentary suggests) and attempting to make the English meanings clearer than the original text (which the relative smooth reading of the English text suggests) then we might “untranslate” this verse back into a Mesoamerican language model that yields a stripped-down triple modifier of Ammon, with the English required to make better sense of the verse removed: “[they had with them] Ammon; Strong-and-mighty-man-he-was, Zarahemla-descendant-he-was, leader-he-was.”
An interesting aspect of this hypothetical reconstruction is that it focuses on Ammon’s leadership as the most prominent idea, rather than leaving it as a near-afterthought, which it seems to be in English. The Mesoamerican literary device positions the most important item last because the triplet moves the mind to follow and emphasize the sequence.
This comment is a possibility only. It should not be construed as proof that a Mesoamerican language was involved. It is completely possible that this feature appears coincidentally, just as constructions characteristic of Hebrew might also occur coincidentally. Nevertheless, since the reconstruction provides a better reason for the word order than the English translation, it is at least worth noting.