Na, I am sure the problem wasn't as severe in v1.1. I continued an old campaign from 1.1 after installing 1.2. The AI was doing just fine, specially the Romans. They had made substantial gains, specially Brutii and Julii (I being Parhia never met them in combat till v1.2). After installing 1.2 I couldn't understand why Brutii which was so strong couldn't even take the two rebel settlements it would lay siege to every other turn and then break away. It went on for 50 or so turns. I play very slowly and micro-manage everything, hence quick saving/loading is a norm for me. This was true for 1.1 and never hurted the AI like this.
I did extensive testing after reading this thread. I never jump on the band wagon without first testing something myself. I have too much faith in CA to flame them without good reason (well I still can't flame them, they hold a special place in my heart... hehe). My tests confirmed that AI armies not only lift sieges, it always tends to completely walk away from the said settlement as if it has completely forgotten what it had set out to accomplish. Only to repeat the process ad-infinitum.
I thus played yesterday for 8 hour at a stretch without loading once and because i am quite further down my existing Parthian campaign, I only got some 5/6 turns done. And guess what, the Brutii finally took those two rebel settlements that they couldn't for the last 50 turns. They also laid siege to two other towns. Same with Scipii and Julii who each took one settlement and laid siege and maintained it, to atleast three more. However, after 8 hours, i had to save and go to sleep, and when i reloaded later, the AI had forgiven/forgotten its enemies/goals and walked away from all its previous sieges. When I say walked away, they had moved their sieging armies a whole turn length away from the previously sieged settlements.
Hope this helps.
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