Wierd and strange bug.

[Trithemius]

I've had my line units decide to deploy in curious fan-shaped patterns instead of to the firing steps in at least one large siege. Quite annoying, as there is no point in practicing your choreographed display marching if the enemy takes our castle and slaughters the garrison! :(

Additionally, just like your AI, some of my units refused to redeploy off the firing steps; some would only do it if I moved them off, then back on to another wall section.