Tueller Drill and Knives: Myth, Fantasy and Reality

2) The Tueller Drill is an interesting thing. Read more about it here and here. It is also known as the 21 foot rule and that name is probably more accurate. The drill itself isn't so useful, it is the rule that comes from it and the well tested scientific evidence behind it that are useful. Basically the jist is that it takes right about as fast for a guy with a knife to cover 21 feet and presumably shank you as it does for a reasonably trained individual to draw and fire an accurate shot. It really is useful as an educational tool and protection for armed citizens should they face a goblin with an edged or impact weapon. It helped scientifically dispell the lawyer and prosecutor based idea that guns are magical talismans and unless a guy with a knife is 3 feet away you shouldn't be able to defend yourself. In short the 21 foot rule did a lot to break down the myth that guns are some sort of a magical talisman.

http://tslrf.blogspot.com/2011/01/tueller-drill-and-knives-myth-fantasy.html