Is the martial arts choreography in the 2010 remake of Karate Kid realistic?

In his article "The Karate Kid: Behind the Scenes," Tim Nasson interviews the cast and crew of the film. This film is connected to the original in theme and story, though the protagonist this time learns a version of kung fu rather than karate:

When the filmmakers decided to open up the movie and go to China, one change that became necessary was the fighting style that Dre would learn. He would learn a Chinese fighting style, rather than karate, which originates from Okinawa and Japan...

In The Karate Kid, Dre learns wushu martial arts, a physically demanding, active kung fu sport taught and practiced in China. He was trained by Wu Gang, the stunt coordinator for the Jackie Chan stunt team, which is responsible for the stunts in the films that Chan directs. Master Wu, as Jaden Smith came to call him, trained Smith for three months in Los Angeles before the production began in Beijing, then continued to train him throughout the four-month production. “When I first met Jaden, he was just a kid,” says Wu. “A few months later, he was at the same level as kids that have been training for five or six years. He was very focused, very talented, and never complained. I’m very proud of him.”

They were starting at the beginning. “Whenever I teach anyone kung fu, but especially a kid, the first thing I teach them is respect for other people. Kung fu isn’t about fighting, but about helping people,” says Wu.

From there, Wu began training Smith in wushu. Despite the fact that they were making a movie, Wu says that the filmmakers were never tempted to rely on moviemaking tricks to make Smith look like he could do something he couldn’t. “No matter what, he had to learn how to move, how to fight, the basic training. There was a serious need for real kung fu, wushu learning.”

Of course, Smith and all of the other kung fu kids would be taught how to fight for the camera in a choreographed match and look good doing it on the big screen. “All of the kids in the film are full time wushu students, but none of them had movie fighting experience,” Wu notes. “It’s not easy to get the timing, the rhythm, and the reaction when you get hit. Also, the drama and the acting in the fight are just as important as the action – the kids needed to tell the dramatic story of the fight with their faces and bodies. It’s very challenging. But the big difference with this movie is that the movements are real.”

I would say that the tournament is fairly unrealistic. Apart from the level of savagery which is unlikely in a tournament of that age category it suffers from too many 'big' moves. I have fought several times under various rule formats and the moment I see a large 'flowery' move I, basically, run forward and throw punches. Their technique does not land 'cleanly' hence they do not score and as it does not land cleanly it rarely hurts. A genuine combatant would not stay in at the correct range (or conveniently move to the correct range) long enough for the majority of these techniques to land unless the skill difference was absolutely massive.

Movie combat is very rarely realistic because realistic fights are quick, graceless and over pretty quickly. Martial art tournaments normally have fighters sticking to a few techniques they know well which optimise the rules set but are rarely as clean and polished as you would see here. The original Karate Kid had far more plausible tournament fighting (apart from the Crane kick - your opponent would simply move to the side and charge in) and also tournament admin (although that is not what you are asking I guess).

From the insultingly stupid movie physics website:

A western style boxer must move to within an arm's length of his opponent in order to land a punch. The punch's time of travel to its target will be less than 0.1 second--barely enough for an opponent to see it coming let alone respond. Needless to say, if the opponent's arms are even slightly out of blocking position or he fails to realize that a punch is about to be thrown, he's going to be hit.

Likewise, if the person throwing the punch misjudges the location of his target or it unexpectedly moves, he's going to miss. Mid-course corrections of a punch are next to impossible to make. If the puncher develops the bad habit of preceding his punch with any type of unnecessary motion, such as slightly pulling his hand back before striking, he warns his opponent that a punch is coming. It's going to be blocked. Although punching looks simple, it takes countless hours to perfect.

Properly throwing the punch is only part of the requirement for winning. Boxers bob and weave in seemingly random ways to confuse their opponents but also because moving targets are harder to hit. It takes a considerable amount of strategy involving jabs, feigns, and footwork to set up the openings required to land a powerful punch. If the the punch fails, the boxer is now in range for a counterattack.

Some martial art styles completely avoid high kicks for just such reasons. To reach an opponent's face, a foot has further to go than a punch, thus taking more time, which a defender can use to detect and counter it.

For the final dramatic kick in the movie, the current karate kid (Jaden Smith) stood perfectly still then jumped upward, rotated his body, hit his opponent in the face, and ended with a perfect landing after a 360º flip all using only one leg. Like the boxer, before making his move, the current karate kid would have needed to accurately estimate the final position of his moving opponent to actually hit him. His ability to alter his trajectory in the middle of the kick would have been limited. Likewise, his timing would have needed to be perfect. If the kick were executed a little too soon or late it would have missed. Compared to a punch, his opponent would have had lots of time to see the kick coming and respond.

When the foot found its target some of the kicker's rotational momentum would have been transferred to the opponent. The more forceful the kick the greater the loss of rotational momentum, the more momentum lost, the greater the chances that the rotation and landing could not be completed. Of course, choreography, dramatic music, sound effects, camera and editing tricks along with wire work can make even non-martial artists look like power rangers.