In Arma the default combat/aware stance is Unrealistic. see my in game picture.
Try standing like that in the picture, go ahead. Make sure your knees are bent like that and your back is hunched over.
Feel like a comfortable position to fire a gun from? Forget firing a gun, Just keeping that position for more than a few minutes is exhausting .
nobody stands like that, look at every picture of the iraq/afghan war and see if you can see a single US marine or US army soldier standing like that in combat.
Look at my included combat photos showing many US soldiers in firing weapons in Iraq/Afghanistan.
Note the positions, Always at least one leg is straight to support body weight for a stable firing position.
The back is hunched much much less. It is most comfortable to fire accurately when standing mostly straight up.
BIS needs to adjust the animations to include more time when the soldier is standing like in those combat photo. {F22271}