A last stand could have been presented heroically - Dupont had, of course pressed a defeated enemy too enthusiastically and got cut off...(cf Vandamme at Kulm) The brave handful who cut their way out and brought the news to Madrid would have been the heroes of the piece. Dupont would be dead or a prisoner and unable to give his version (cf Vandamme..). You can see how much more satisfactory that would have been.
Susan