The tape might actually teach you some good techniques, but as alluded to, they will not do you any good until you practice them repeatedly and develop the muscle memory necessary for clean execution and confidence in your abilities.
Not sure on the price, but a good dojo/gym/training facility that teaches good hands-on lessons and practices with resisting opponents is the way to go.
Here is a good example. Some may practice disarming with a wooden or rubber knife. Try practicing with someone trying to stab you with a magic marker and look at all the marks when you are done. Extrapolate this to a "fake gun."
Certainly learning any technique is better than attempting such disarms on the fly without prior practice. Indeed, several successful mixed martial artists have done well in the ring learning from videos. I'm just saying that the quality of the time you spend focusing on such matters (training) is done in as realistic an environment as possible. IMO the worst thing is a false sense of security.
