Since "Mastering Jiu Jitsu PDF 21 Exclusive" appears to be a specific search term or a niche digital product title (likely a collection of techniques, a specific ebook, or a marketing lead-magnet), I have prepared a comprehensive white paper that interprets this title.

Every submission is a lever (bone) on a fulcrum (joint). The exclusive concept is the Fulcrum Triangle: the closer the fulcrum is to the joint, the less strength is needed. For armbars, the fulcrum should be 1 inch above the elbow, not on it. For choke, the fulcrum is your radius bone on their carotid.