There is a picture in our training hall of our Grand Master, Chun Sik Kim, splitting a soda can in half with a sudo speed break. A speed break is a karate strike in which the object to be broken is not held in place. In this case the soda can is merely sitting on a table. Master Kim hits the can with such speed and force as to cut it in half. Impressive! Personally, I always use the little pop-top to get to the liquid inside, but to each his own.
You no doubt have seen demonstrations where black belts break bricks, concrete slabs, and even large blocks of ice as a demonstration of their tremendous power and concentration. As a tournament judge, I often have to compare one set of breaks against another. I'll explain my criteria in another post, but for now, let's just say that power isn't everything.
Consider the sequence of moves to the left. This is a pictorial representation of one specific technique known as Ho Sin Sul, Two-on-One Grab #2. The attacker has grabbed the artist's right wrist with both of his hands holding very tight. You may or not be able to follow the description below of how to defend against this grab - and that's OK, the point will be obvious.
The artist begins by bringing both of her hands together palm-to-palm as if beginning to pray (A). She then rotates her hands around until she can grab the attacker's wrist with her right hand and push against his elbow with her left (B). She keeps pushing until the attacker bends over (C) at which time she executes a downward strike with her left elbow (D).
Here's the point; sometimes I am asked where exactly should the downward elbow strike land. Should it hit the attacker's elbow? Should it come down on the back of their triceps, or their back, or maybe even their neck? I've seen advanced students debate the 'correct' answer, even consulting their notes and their seniors.
The correct answer is based on the context of the event. Let's say you are having a good time a family reunion (oxymoron?) when suddenly Uncle Gordo and Cousin Lenny start a shoving match. I'm betting that this might happen after the introduction of alcohol. You try to break up the judgment impaired intoxicants, when one of them grabs your wrist with both of his over-sized man paws.
You begin to execute the aforementioned extraction technique, and because of your repetitious rehearsal, your technique is flawless. All that's left is for you to perform the downward elbow strike and your reputation as a Shaolin Monk will be forever cemented in family lore.
Context. This is Uncle Gordo we're talking about. This is not some street thug after your money, your identify, or your life. This is a guy who drank too much and whom you will likely to have to face in the very near future. Permanently paralyzing him from the shoulders down seems like an over reaction to his shoving Lenny. Maybe a simple charlie horse on the back of his triceps is a suitable ending to the push-o-match.
Context. If this little attack had happened in the mall parking lot after the close of business and you were alone, and two more assailants were running toward your location and you only had a moment to free yourself, and you need to make sure that the attacker could not chase you - - then maybe striking the back of his neck with the point of your elbow is warranted. It's all about context.
So, there is no 'correct' answer, at least not in the sense of 'always strike the arm, ... or the back, ... or the neck.' The right answer is, 'what is the context of the attack?' The answer to that question, will likely determine when and how to strike.