Smart Byzantines

I recently started a campaign as Venice. I took the rebel areas next to the byzantine empire rather quickly, and it was a bit tricky as I did not have good quality troops.

After this, I started garrisoning the settlements (2 castles and one city).

Based on my previous experiences with keeping defenses up, I stationed some extra cavalry in the settlements right next to the Byzantines and thought that they will attack in time...

They had two stacks of troops, which eventually approached me, crossing the border even.

I then decided that I do not want to defend a city (cannot remember the name, but above greece on the coast facing italy) and I removed my army to Ragusa in the north leaving a minimal garrison. To my amazement the Byz stacks retreated once my troops left the province.

So, this leads me to think that the AI decided to make a pre-emptive attack based on me having an army capable of taking a city from them. So they sent 2 stacks to remove a threat. Once I left, they left my city alone and went to battle the Hungarians...

So now I have been in war with them for ages, but they still leave my city alone unless I send more troops in there.

Has anything like this happened to you?

With the hungarians I had the exactly opposite experience and they tried to take my castle with a min. garrison - I was even at peace at the time.

I have had similar things. The problem is how to decide if it is "smart AI", or just over cautious?

To date I have not had a single seige played out on the battlemap..with my army as the defender. I find this kind of strange. Plenty of seiges (though less than RTW in general) on the campaign map..but they often retreat. Or sometimes just hang about after they have built their seige equipment..far too long not assaulting me..are they waiting for the full duration all the time? Hard to say..but their strategy isnt working.

I then counter or move units into defend...the enemy in general retreats and does a runner. What is making me thing that this isnt smart, is that plenty of times France (I am playing as england), could have taken back settlements if they had assaulted as soon as their seige gear was ready. Upshot of this is I pummeled France into the ground..only when they were down to their last two regions did they really fight back. They are now all gone.

I have seen this pattern from many other factions too..so I dont think it is a specific trait.

So in short..so far. I am leaning towards over cautious....and not that smart.

You still have to consider that they actually did not escape my troops, but rather, they left when my troops left. This happened a few times. They only crossed my border to attack my city when it held a whole stack army of my troops. When I reduced the stack to 3-4 militia, they left and did not try to take the city.

The reason for them not taking the city is escaping me though, as I still think the AI is not smart enough to figure out that some settlements are hard to keep once you take them. That one would have been such a case, as my army would still be withing 2 turn march of the city.

I'd call it smart.
The AI perceived you as a possible threat. After you left there must've been more immediate threats at hand, such as the Hungarians. Maybe the AI also wanted to scare you off but didn't want to wage war?
So far I've not seen much outrageous stupidity from the campaign AI. In fact it's very clever with its agents.
BTW, I've just posted in the Venice guide section. You may find some ideas for your Venice campaign.

R'as