hmm, please correct me if I'm wrong, but I remember that I was browsing through MTW's files a while ago, and I stumbled upon the one encoding tactics and such.
It was also a text file, so, at least theoretically, it should be possible to mod it such that the AI employs new or at least different tactics on the battlefield.

Since I am not a frequent visitor on the modding boards, has this been ever addressed ? Is it a non-issue (i.e., perhaps, for instance, it is not moddable at all because it is too tightly coupled with hardcoded things) ?

I'm probably not gonna have enough time to figure out the file and mess with it to see if anything can be done, but IF it COULD be done, then that would be a fabulous answer to your problems, even though perhaps not the one you expected, eh ?