Quote Originally Posted by Satyr
"The algorithm of least astonishment!"

I love it! That is exactly what one should expect in a game. That is no where near what CA ever provides. It seems to me that either CA needs a better project manager/lead programmer, or better structure design in MTW. They just seem sort of overwhelmed and keep introducing the same mistakes over and over with no consideration for your rule. After playing with the patch, I am not even sure they understand how their monster works and they certainly can no longer control it. Hopefully the tools they have provided to the community to mod with are sufficient to make up for their deficits.
Okay, but look at what the OP said about the unexpected action of the Scottish AI:

So what does the Scottish AI do?

Remember the The algorithm of least astonishment?

They sail past all those prime and logical targets, and they declare war on me!

Well, we'll see what happens when scads of armored highland nobles meet scads of Huscarls. I have a feeling they'll fight hard since they fleet they sailed over on is now gone.

It was too late last night to start the slug fest, so I'll try it tonight.

But in a way I'm glad its happened. It certainly spiced things up a bit.
Don't underestimate the power of astonishment, people. It's what can make a game interesting and have replay value, even if we're not sure if the wackiness is due to actual bugs, or just random factors.

Do we want the conquest of the map by the AI factions to follow a script that plays out exactly the same way each time? Or do we want different, "emergent" outcomes every time we play a new campaign?

Speaking for myself, I don't want to see absolute craziness, but I also don't want a predictable game where I can safely assume that Faction A will always do this, and Faction B will always do that. It's a question of balance, and maybe some "odd" or even buggy decisions by the AI are necessary to keep things unpredictable and challenging.