[Arker]

Testing reveals that switching the final order from 'stay behind troops' to 'cast spells' or, for that matter, to null, does not alter the behaviour. I still get mages running across the battlefield to get close to other mages, archers, or illithids and casting BoW. There is some variation, though, sometimes cast BoW THEN run to where it can inflict the most casualties on their own side, sometimes run to position first, THEN cast BoW.

*sigh*

I don't know which is dumber, the mage doing that in the first place, or the other units inside the area of effect simply standing there until they die from it, but either way, there's a stupidity overload going on for sure.