fine fine, let's call it 15~20% at most
It all depends on how well someone can aim a weapon in the middle of combat. I'd call it 85%+ in an urban environment.
In real war people actually listen to squad leaders and commanders.
In real war people actually move in a squad.
In real war people have a set role in a squad.
In real war people use cover 96% of the time.
In real war people carry only one rifle.
In real war people don't throw grenades randomly.
In real war people breach doors and clear as a team.
In real war people can't pilot every vehicle, and can't operate every weapon system known to man.
In real war people check for civilians.
In real war you can hear a gunshot from miles away.
In real war silencers don't lower the sound enough, it only scatters it.
In real war the military hardly ever uses shotguns.
In real war all branches of the military work together in some way.
In real war people care about someone being shot next to them.
In real war you can't regenerate your health in 6 seconds.