The Lamanite flight led to confusion in the ranks and therefore less ability to mount an organized fight when the Nephites engaged them. It is not, therefore, overly surprising that there were no Nephite deaths. Even though there were no fatalities, however, there were certainly casualties from wounds and accidents. Nevertheless, it is also likely that Mormon made sure to include this piece of information as a parallel to the miraculous survival of the 2,000 stripling warriors. While the story itself is not as miraculous, the point of the salvation of the righteous is the same.