But brining a weapon to your shoulder to fire it is not just about stability, it's also about firing a weeping in a straight line from eye to target via the weapon, you do't get that when shooting from the hip.
As someone who knows something about weapons and martial arts I always found it irritating when people who write about it has no idea, if you write about combat know something about it, don't just think cool. It's like when there is no science in sci-fi.