[LDiCesare]

I tried the following:
7 commanders in the center with 120+ units on the sides and rear:
First thing the commanders do is move backwards. Stay behind troops.
Repeated the test with units on the side, not on the rear, and one commander in the front:
Same thing. Stay behind troops.

I consistently and always get a Stay behind troops behavior (except for mages who cast spells).
I tried with and without mages, mounted, chariot and on foot, with several squads and only one squad on the sides and/or behind, commander in front and in the middle.
I never saw a commander without orders attack when he had troops to lead (except for the usual stuff like being the last fighter, having only one soldier left, going berserk etc.).