When Ralph Macchio and company signed up for The Karate Kid, none of them knew much about martial arts. Sure, William Zabka was a wrestler in high school, but shooting for takedowns isn't the same as throwing roundhouse kicks. So to get them ready for a karate tournament, the filmmakers called in Pat E. Johnson. This guy had studied tang soo do while serving in Korea, and when he returned to America, he joined up with Chuck Norris, working at one of Norris' schools. Soon, Johnson racked up an impressive fight record of 196 victories, one loss, and a draw, and not only would he go on to work with stars like Brandon Lee and Jackie Chan, he also had a part in Bruce Lee's Enter the Dragon.
In other words, Johnson's combat skills were as legit as they come, and when he was hired as Karate Kid's fight choreographer, he got pretty creative when it came to instructing the actors. For example, he taught Macchio and Morita together so, as he put it, "they would share their aches and pains like two little old men, and they built camaraderie through the training." He also made sure to train them in a very relaxed atmosphere, similar to Mr. Miyagi's style.
However, Johnson took a very different approach with the Cobra Kai. He basically put them through boot camp, forcing them to do push-ups and treating them like soldiers. As for the actor who played Kreese, Johnson explained on a DVD special feature called "Beyond the Form" that he wanted William Zabka and the rest of the kids to view Martin Kove as an experienced black belt. To create this illusion, Johnson trained Kove privately, keeping him away from the rest of the bad guys. That way, when Kove met the rest of the crew, they would view him as a real martial artist and treat him more like an actual sensei.
Johnson's methods were pretty clever, but his work on The Karate Kid wasn't all just behind-the-scenes. The next time you watch the film, pay attention during the karate tournament, and you'll see the fight choreographer playing the part of a mustachioed referee.