This was posted by Dutch of CA @ .com
Very useful info.The AI does go to quite a lot of trouble to evaluate troop strengths of groups of units against other groups - taking into effect a lot of fairly detailed things like frontage, unit disorder, relative kill rates and morale. Flanking sub-objectives and so on play a big role as well.
But there is a chunk of code of last resort, which is there so that something gets done when there are no good choices, and that generally tries to find a weak point for the strongest unit to attack. This is the code which was referred to in the comment above - what it says is a layman's simplification of a part of a system, and shouldn't be taken as gospel as to what precisely is done or not.
Hopefully that clears up any misunderstanding...
He then added this in a subsequent post:
The problem is, sometimes using the general's unit as a battle-line-breaker is the right thing to do, and a very effective tactic. Especially if the army has few units and/or a lack of armoured troops. It's just that identifying those cases, and discouraging the remainder, has proven a little tricky. The AI as a whole has been one of the areas which we have been focussing on, for, um, "future products".
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