the video is teach you how to be a fake. In reality, you can't really fake something for a long time because others will see through you. So,you are either a natural leader, or a follower. You are either good at something and have the confidence that comes with it, or you are just crap. You can't fake these with body language. Thus,
body language always plays an important role, not just in work but in life as well. It helps us to easy communication in some cases. Let's study and apply body language in work & life