Very disappointing news about AI combat spell use

[PvK]

Heh! I was wondering if the AI would ever creatively decide Vortex of Returning by itself.

Just marking Vortex of Returning as "AI never casts" would be a crude but simple solution. But I think there is a counter-argument, which is that, in an ideal world, there would be enough time to program the AI so that it sensed when its own troops were in grave danger of being wiped out, and the home province was safer, and only in those circumstances to cast that particular spell.