Don Troiani comes from a tradition of military art history painters, including Detaille and Meissonier.
From my understanding, classical painting started during the Renaissance with its emphasis on biblical subjects and stories from antiquities. This evolved into neo-classical art capturing more contemporary themes, starting with JL David and progressing thru his later successors, JL Gros, Delacroix and Delaroche to give history painting.
These worthies never painted that accurately anyhow (David and Gros painted propaganda for Napoleon), Delacroix fudged details and moved in a Romantic direction, Delaroche painted Napoleon crossing the Alps on a mule (who's to say what colour the mule was etc) but the whole world prefers JL David's more spirited painting.
Troiani is a fine painter. We should accept that reconstruction in history paintings is inevitably flawed. These paintings recreate a moment in our history, much as museum reconstructions and whilst museum displays may sometimes be corrected due to public feedback, I doubt that paintings are that easily corrected.