Siege Cavalry question

[Lord Fluffy]

I've had a few like that when in a fortress or citadel. You see 1 or 2 unit moving way ahead of the others and getting themselves slaughtered.

[Foz]

Probably the AI decided immediately that it should rush the square since there would be no resistance anywhere else... and it doesn't know enough to keep faster troops even with slower ones. Consequently, the AI units pull apart from each other and arrive at different times, presumably because it just ordered 1 attack command to all units from whenever your walls got breached. If you had units at other places in the city to give resistance, it would probably be less likely that this would happen. The AI would devise more interesting plans (okay, maybe only slightly, but still) to take on the nearby threats, and afterwards probably end up at the square in a much more cohesive fashion.

[Lord Fluffy]

The one time that I remember rather well, I was in a fortress with a somewhat minimal army. The enemy spy had opened the gate and launched a surprise attack. The first thing I did was pull all my soldiers to the inner wall. So that would agree with your theory there Foz.