My memory goes back to a discussions by and between George Dillman and Earl Montague. Mr. Dillman holds quite a heavy stock in the use of pressure points, I believe his theories are based on several strikes are required to open up simplistic KO's. One in particular was to strike two on the arm to "open" the one in the neck, causing a KO. Mr. Montague pointed out that a KO was possible without the need of the "opening" techniques as a KO was achieved by compressing the carotid sinus. Certainly KO's are possible without pressure points, but I have used certain ones to gain compliance quicker when grappling. This is all well and good in training, even against a resistant opponent, but what about transfering them into a real fight? How well do they hold up, if at all?