On the ground (e.g. during Non-Technical OS-INT), many unforseen small conflicts may arise. The ability to think on your feet paired with an ability to read people's basic statistical probabilities and a sense of charisma can make the difference between exiting the conflict unscathed and tanking the excursion.
The ability to follow the same basic skeleton of social engineering procedures helps shape one's ability to assess a conflict, identify goals, assess resources available based on general statistical knowledge, plan, and launch an attack that will neutralize the conflict while protecting the asset/target/bystander.
Discusses basic tenets of certain aspects of psychology, sociology, anthropology, etc., to pull together strategies to assess, formulate, and launch on the fly as the situation demands.
Also makes fun time-killer when out on the town.