The "AI changes" were (according to the programmer who did it) a complete rewrite of old code because the old code was too inflexible to handle NPC as well, especially bandits. So a rewrite was done more than 3 years ago that could accomodate anything from dumb (for zombies) to intelligent (for bandits and NPC). Just that "dumb" didn't mean exactly like with the old AI code but a different sort of "dumb".
It was not a reaction to any cheesy player bases. It was work that had to be done for bandits. Case in point, the new AI can be cheesed as well, that wasn't the goal.
Your proposed solution is not a solution for TFPs problem. And their new AI is probably widely used right now to make the bandits work well, so there is no chance in hell they will ever go back to the old AI. Your only chance is to hope for a modder to implement some A16 AI compatibility mode inside the new AI.
PS: Tastes differ. I like the new AI much better than the boring old AI.