This might be a fun exercise for people to try. In order to get the most out of it, step away from your keyboard and actually do these moves as I describe them. These arts comes from Wabjitsu-do (I am a 21st dan Grand Soke Master in Wabjitsu-do 
). For reference, see the first application of the knife hand block in this video (from earlier in the thread). I want you to do 3 different techniques, but the hand motions will be exactly as shown in the first application in the video.
Technique 1 - Cross Block - This technique is similar to the first application in the video. The chambering hand is the blocking hand in this case. However, it is not a parry, but a strong knife hand block. If a straight punch is coming to your face, the "chambering" hand crosses your center line, the knife edge blocks the forearm of the punch hard enough to break the forearm, or at least seriously deflect the punch. Then, as the same hand extends back, it is merely measuring distance, feeling the opponent.
Technique 2 - Under Punch - (this is shown once in the same application in the video) As the chambering hand chambers, the other hand delivers a straight punch underneath. This is a hard punch, intent on breaking the short ribs. The chambering hand can be seen as a parry, a distraction or a cover, but the technique here is the straight punch. After the punch is delivered, the chambering hand extends, measuring distance.
Technique 3 - Knife Hand Block - This is the block as normally done in Karate or TKD. The hand chambers, then fires a strong block, using the knife edge of the hand. Exactly as done in Karate and TKD.
First, do each of these techniques 20-50 times. Or at least enough that you can develop speed, power and control to deliver the block or punch as indicated in the technique. Once you can develop reasonable speed and power, focus on what your body needs to do to accomplish that. What are your shoulders, hips, legs, weight, momentum, torque, feet, ... what are they doing? In all 3 techniques, you will find that your body must move very differently in order to accomplish the intended block or strike. In order for me to accomplish #1, I use a lot of my abs, contracting... it almost feels like a crunch, the power is in rotating towards the back side. In doing #3, I don't use my abs at all to crunch, the rotation is in the opposite direction. In addition, there are a ton of other changes that need to be made to generate and apply force in these 3 areas. In each case, your arms and hands are waving the same way.
Please, do not try these in your school, do not believe that these are martial techniques... unless your check clears, then I will send you a Multi-Dan certificate that you can frame (cash works too)
This is why techniques are named or described as what they are. If you really break down all the motions, and muscle movements required... it will take a lot of time, and be very hard to teach. By teaching this movement as a "knife hand block," people will produce the correct body movement. If you tried the exercise above, you found that you had to experiment a little, in order to put the force where it needed to be. This way, you could define the start pose, the end pose and the path between... but by specifying that it was a knife hand block, with the outstretched hand... it tells you where, when and what direction to generate the force. This causes your body to move a certain way. That is the purpose for the technique, to move your body to generate and control this specific force. Once you can do that, there are a lot of ways to apply that force or that body movement.
In this case, you can do the entire body movement with very little help at all from the other hand. We can easily find other arts, using a similar block, but with different hand placement, or even no hand placement of the other hand. They may leave it in guard even, and still develop the same power on that block. So, each art puts that other hand in a place that they like. Some favor keeping their guard up, some favor prepping for the next attack... here, depending on what they feel is the next attack, may determine where it goes. Some, may just like the way it looks in a certain place.
So, when I learn a new technique, I learn it as a beginner. "This in an upward block, that will break a baseball bat being swung down at you." Ok. I practice and learn that block, with that intent in mind. I don't really believe it will break a bat or even stop a bat... but I do it with that intent anyway. As I get more comfortable generating that intent, now I can start studying what those postures and intent are causing my body to do. What it is causing my body to do, is the whole point, thats what I need to learn.
Think of Judo. They teach you to grab the other guys lapel, then push a little and pull hard, then you step in and throw the guy. Where the lapel is, doesn't matter at all. You can pull it as far as you want, it doesn't matter. What does matter, is the structure and balance of the other guy. When you pull, you are effecting their structure and balance. If the other guy has a super loose gi, you might need to move his lapel much further, in order to move him. It does not matter how good you are with gripping or moving the lapel, if it never effects the other guy's body.
So, naming a movement a upward block, or straight punch can be thought of as the "gi lapel" your instructor is pulling, to put your body through the correct sequence. As you learn the body sequence, you no longer need to be pulled through it, but can now find your own ways to apply that sequence.
Now our katas and forms become more than just a dictionary of movements. They become like the rules of grammar for your language. How do different movements fit together, how do they effect one another, how does their meaning change in context? As you learn the grammar, you become an author... and authors occasionally break the rules....
). For reference, see the first application of the knife hand block in this video (from earlier in the thread). I want you to do 3 different techniques, but the hand motions will be exactly as shown in the first application in the video.Technique 1 - Cross Block - This technique is similar to the first application in the video. The chambering hand is the blocking hand in this case. However, it is not a parry, but a strong knife hand block. If a straight punch is coming to your face, the "chambering" hand crosses your center line, the knife edge blocks the forearm of the punch hard enough to break the forearm, or at least seriously deflect the punch. Then, as the same hand extends back, it is merely measuring distance, feeling the opponent.
Technique 2 - Under Punch - (this is shown once in the same application in the video) As the chambering hand chambers, the other hand delivers a straight punch underneath. This is a hard punch, intent on breaking the short ribs. The chambering hand can be seen as a parry, a distraction or a cover, but the technique here is the straight punch. After the punch is delivered, the chambering hand extends, measuring distance.
Technique 3 - Knife Hand Block - This is the block as normally done in Karate or TKD. The hand chambers, then fires a strong block, using the knife edge of the hand. Exactly as done in Karate and TKD.
First, do each of these techniques 20-50 times. Or at least enough that you can develop speed, power and control to deliver the block or punch as indicated in the technique. Once you can develop reasonable speed and power, focus on what your body needs to do to accomplish that. What are your shoulders, hips, legs, weight, momentum, torque, feet, ... what are they doing? In all 3 techniques, you will find that your body must move very differently in order to accomplish the intended block or strike. In order for me to accomplish #1, I use a lot of my abs, contracting... it almost feels like a crunch, the power is in rotating towards the back side. In doing #3, I don't use my abs at all to crunch, the rotation is in the opposite direction. In addition, there are a ton of other changes that need to be made to generate and apply force in these 3 areas. In each case, your arms and hands are waving the same way.
Please, do not try these in your school, do not believe that these are martial techniques... unless your check clears, then I will send you a Multi-Dan certificate that you can frame
(cash works too)This is why techniques are named or described as what they are. If you really break down all the motions, and muscle movements required... it will take a lot of time, and be very hard to teach. By teaching this movement as a "knife hand block," people will produce the correct body movement. If you tried the exercise above, you found that you had to experiment a little, in order to put the force where it needed to be. This way, you could define the start pose, the end pose and the path between... but by specifying that it was a knife hand block, with the outstretched hand... it tells you where, when and what direction to generate the force. This causes your body to move a certain way. That is the purpose for the technique, to move your body to generate and control this specific force. Once you can do that, there are a lot of ways to apply that force or that body movement.
In this case, you can do the entire body movement with very little help at all from the other hand. We can easily find other arts, using a similar block, but with different hand placement, or even no hand placement of the other hand. They may leave it in guard even, and still develop the same power on that block. So, each art puts that other hand in a place that they like. Some favor keeping their guard up, some favor prepping for the next attack... here, depending on what they feel is the next attack, may determine where it goes. Some, may just like the way it looks in a certain place.
So, when I learn a new technique, I learn it as a beginner. "This in an upward block, that will break a baseball bat being swung down at you." Ok. I practice and learn that block, with that intent in mind. I don't really believe it will break a bat or even stop a bat... but I do it with that intent anyway. As I get more comfortable generating that intent, now I can start studying what those postures and intent are causing my body to do. What it is causing my body to do, is the whole point, thats what I need to learn.
Think of Judo. They teach you to grab the other guys lapel, then push a little and pull hard, then you step in and throw the guy. Where the lapel is, doesn't matter at all. You can pull it as far as you want, it doesn't matter. What does matter, is the structure and balance of the other guy. When you pull, you are effecting their structure and balance. If the other guy has a super loose gi, you might need to move his lapel much further, in order to move him. It does not matter how good you are with gripping or moving the lapel, if it never effects the other guy's body.
So, naming a movement a upward block, or straight punch can be thought of as the "gi lapel" your instructor is pulling, to put your body through the correct sequence. As you learn the body sequence, you no longer need to be pulled through it, but can now find your own ways to apply that sequence.
Now our katas and forms become more than just a dictionary of movements. They become like the rules of grammar for your language. How do different movements fit together, how do they effect one another, how does their meaning change in context? As you learn the grammar, you become an author... and authors occasionally break the rules....
