Why are stances so important? Why are body mechanics, i.e. proper alignment, breathing, centerline, spinal alignment, limb alignment, structure, etc.? When I think of martial arts today I tend to think of what they can teach us for self-defense. You have read my posts lately and may feel I don't think MA contributes a lot, modern or traditional, to self-defense, i.e. techniques that are more inclined toward sport or as Rory Miller quoted "dueling." That is not true because the one major thing that martial arts contributes toward our ability to defend and avoid are things such as the above mention physiokinetic aspects and lets not forget those theories and philosophical teachings (think mind-set here).
Back to stance and body alignment, structure, etc. Let me quote from the fundamental principles of martial systems. "A properly aligned punch will take our own joints to a constructively 'locked' position, removing enough slack to create the stability required to deliver force."
This is just one aspect of what it takes to learn a martial system and these benefits as explained here and in the fundamental principles of martial systems are those things that contribute a great deal toward avoidance and self-defense.
Avoidance comes from the philosophical teachings that create a mind-set similar to what the military create in a mind-set that allows them to be what they can be in defense of our country and way of life. Similar is important here because although the essence is the same the strategies and tactics are different. Avoidance comes from the control you learn in martial arts. It is training the mind to stay in the moment leaving conscious thought outside allowing you to see, hear and do things that will not exacerbate a conflict. It is leaning about applying things properly. It is about learning to see all aspects of violence and recognizing when your mind is dropping into ego pride driven monkey crud. It is leaning to recognize that face is important and that allowing an out allows us to avoid. It is learning that pride and ego are dangerous in a conflict and that letting go is important to avoidance. It is learning the in's and out's of violence in all its forms so you can recognize and deal with it appropriately. It provides you fundamental methods to deal with stress and chemical releases of the body and mind. This and that and so much more provided the training and practice are appropriate to self-defense.
It teaches you the things you use to supplement reality based self-defense training even if it is not truly a self-defense system, i.e. once the conflict goes physical. The disparities between modern martial systems and self-defense are there and should be understood. This would allow you to achieve many things without mixing it all up.
The self-discipline, self-control and self-confidence attained through martial arts training and practice go a long way toward creating the same in life even if you don't need self-defense. Well worth the journey and lets not forget the health, fitness and well-being that comes from martial arts properly taught, trained and practiced.