Like everything in the universe, grappling conforms to the laws of physics. When teaching certain techniques, it’s best to frame the instruction in terms of geometry and the physical principles involved. The 90 degree rule is important to remember, especially when fighting a much larger and stronger opponent. The angles of your attacks and defenses increase the power with which you can execute the techniques. This is a clear and succinct explanation and demonstration of a basic but fundamental principle in grappling.