On the one hand the AI shouldn´t do any suicide when outnumbered, on the other hand, they shouldn´t know the exact number of defenders as they do (at least it seems so).
I noticed that whenever I travel even with a small army to a settlement that is about to be besieged by the enemy that they will always divert course, and even when I forfeit the lives of my troops with the massive sneaking in during a seige loss, as soon as I'm inside the enemy will always...