However, some 'dumb' AI manuevers are actually good to make a game ... interestingly more difficult.
In my current game, as Germany (BB = 39), I have a lot of Africa colonized. I was allied to Russia during the France-Prussian War (I always fight France and Austria alone for those events). The alliance was about 1.5 years to expire, when ... Greece DOW the Turks. Russia is allied to Greece, and calls me in as well. UK is allied to Turks. France is allied to Greece. So, reluctantly I am at war with UK. (And France, thru the Russia-Greece alliance is my ally). Well, not much happens. Few provs change hands on the borders of Turkey. Soon, I get a white peace with Turks.
Um, I was at war with the UK. The AI remembered that. And, although there was no combat for my Prussians nor any other animosity (relations were at 117), when the peace expired with UK .. the DOW me in late 1877.
My little navy is caught at sea while ferrying troops. The UK ravages my colonial empire with 50+ divs, 10 were arty. They land in Hamburg and all along the north German coast. 100 Brit div's die in Germany. Eventually, I get a no tribute peace, which costs me 36 of my 4550 prestige.
Peace was in 1882.
Now, after almost 2 years, my industry is starting to come back online. It was around 1300+ or so before the war, maybe higher, and I was making 1600 a day in 1876. After the war, ind rating was 750 and I was losing 600 a day. (saw my 1.3 mil drop to 300k .. bought the Bismarck reform but still lost 500k in there somewhere). And, revolt risk is still high. I have also rebuilt my navy, and it is now stronger than before the war.
So, although the English gained little, it did set back my industry and now I have to stay neutral (which is what I usually do, anyway, but still). Hmm. Kinda makes the current game interesting.
And France? Well, we were allies in that Greek-Turk great war. So, what will they do now? They have not made much of an effort to rampage during this game. Morocco and N African minors are still there.. Turkey nailed Tripoli. (And USA has both Ethiopia and Egypt .. they also freed Canada and smacked UK.)
Chances are, the French AI will attack me sooner or later due to Alsace-Lorraine. They stand no chance but they WILL either DOW me (low chance since their mil rating is 54 and mine is 187) or colonial war on me.
So, some dumb moves by the ai might not be so clearly dumb. I mean, if UK were a player, then the war they had with me would make sense because it fouled up my econ some. And killed off a few soldier pops. Then again, the UK was hurt even more by the war, so I don't know. It will be somewhat interesting to see if France does come after me.
Finally, it would be nice if relations would mean more to the AI for DOW. Not the EU1 way, which I think was too lenient, but a little bit better. (UK really has no business coming after me at this time other than to give me high WE).