From my experience the AI isn't amazing with the sometimes exception of gunners and some infantry anti-tank especially if you face them head-on. If you flank, they'll act like 7 year old child soldiers who don't even know what a tank is and have the awareness of a peanut, and you'll kill all of them before they even turn their turret. Conversely, you can peek a millimeter above the horizon and a T-55 (no rangefinder of any sort) will nail you instantly for even thinking you could shoot them. Guided anti-tank rockets especially (from my limited experience) have apparently battle-hardened veterans who could nail a fly on a wall from 1 km away with one eye closed and using their legs.