I've tried to charge an Arab spear unit on deep stream into Byzantine spearmen, I saw the detail info shew that my spearmen was disordered, but theirs not.
From my current observation, I think it works like below:
If cohort R is in rough terrain and cohort O is in open terrain, both heavy foots,
when R charges / attacks O, R gets disordered, but O doesn't
while when O charges / attacks R, both O and R get disordered.
So, for a medium foot cohort, putting the enemy on rough terrain can gain more advantage than standing on it.
Am I right?


