I would think you could also reason that if you see a friend or two get killed you might get really pissed off and want to get instant revenge with the enemy right there infront of you. And I agree that people fleeing would cause others to flee. Now I wonder if in the code that if some units retreated in a previous round then in the next round they are more likely to. But the cascading thing would support everyone to start to flee at once sorta. I could understand that random individuals would flee from a fight. I just find it weird that there could be four guys on the front line and be like crap our other 16 guys we travel with are dead/wounded, and even though we are surrounded by over 200 other men from our country fighting alongside us we should risk getting killed and run.
Fight or Flight reflex. If Timmy and Jimmy are killed, you may indeed be pushed to avenge them. When it is Timmy, Jimmy and 20 others of your 30 man unit, chances are things will start to seem hopeless and fear will take control. Hollywood heroics not withstanding, this is the norm though of course there will always be exceptions. The French Foreign Legion is an excellent example of a training regime an Esprit De Corps that has resulted in several notable last stands.
I agree again that any sort of fraction of the noble units would make it valid for noble units to flee. The BM battles appear that it is just a giant mosh pit with attackers and defenders merging their armies together. Now with the new unit matching system maybe they are trying to make it so units are split up, but trying to visualize that in a medival setting looks goofy.
That is just how close combat works. Lines meet, formations push against each other and oft time merge before reforming and rejoining the attack. Individual units may try to hold a coherent formation, depending on their training and equipment, like pikemen blocks, and unit may try to position itself relative to its neighbors, but all along the line break through etc will occur. Given the limitations of turn based combat and the visualisation provided you need to imagine a lot of this, but notice that you men always fight as a single group, sticking together within the crush of the fight, and when it comes time to advance again, they do so as complete unit.
Also I had second thought that should improve fluidity to the turn based fighting.
Few problems I see here, first is this
"(1) Note that this is the value where your men will be ordered to retreat. They might still retreat on their own due to fear, panic, low morale and other factors. These factors are totally independent of the value you enter here. The only effect this value has is that if your unit suffers more than this amount of casualties, a retreat will be ordered."
So I would think in general unless you set very low causality levels, that in the example you gave there would be a good chance the unit will have retreated due to morale or something anyway.
The second issue has to do with the order of combat in the game. All hits are allocated before causalities. That means that if a unit decides that it is time to retreat after 1 more man dies, all the other hits against that unit are virtually wasted. A possible exploit of this would be to have a few large cheap units set to retreat at low casualties. Since large units tend to attract a greater percentage of the hits, for at least 1 turn you could render a good portion of your enemies hits ineffective as they are allocated against units that retreat.
