Last time I tried this I found the enemy. You'll that the AI has an artificially higher reaction time than what is possible for human players.
Play in any area that has a lot of visual clutter. AI can see and track through trees & boulders although you can't. It takes a while to figure out what is happening because your screen is flickering back and fourth rapidly until you manage to look down and figure out a tiny bush is causing your screen to flicker. Meanwhile the player gets stuck on a 6 inch tall bush. My entire squad was blown up when an AI team member shot rocket into my back. So if they are shooting and transition to a standing position to shoot at a new target to your right they will continue shooting during the process, muzzle sweep you and empty their magazine into you. The AI continues to shoot at a target even when they are changing stances, from prone to standing.
About half if not more of my deaths are the result of my AI team members shooting me in the back. Too many issues and just outright unfinished features that should have been corrected in ArmA 1. And each time I leave entirely disappointed. Every now and then I give ArmA 3 a go because there aren't any other semi modern realistic shooters out there.