Having numerous opponents attack you in a real fight is the rule rather than the exception. Knowledge of grappling may be a good measure to try and escape a ground fight, but in all reality BJJ, Judo, wrestling, and any other "groundfighting" art will get you killed in a real life scenario.
Take for instance the video footage of a police man who pulled over then unknown drug trafficers. Getting all 3 men out of their car, one made an attempt at a double leg. The police officer tried to sprawl out, but the two other men grabbed hold of him, and drug him to the ground helpless. There they stabbed him to death. Can you really tell me that your training in BJJ, and other grappling systems would help you in this situation? School yard fights are one thing, but in a real world life and death struggle, because you train to go to the ground, to the ground you will go. And no matter what your belt level, 3 assailants will have you at their mercy. Especially if weapons are involved. And they usually are.
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