Well, heck, if you are confused, what hope have we then?
I am sure you have your arms around this, but are asking a rhetorical question for discussion's sake. I am going to insert below something I wrote on the KenpoNet a few days ago and ask for your (and anyone else's) comments in furtherance of the discussion. Because I think the term master key is used where it is not meant to apply by the kenpo community, especially in regards to "master key techniques".
So here is what I wrote, and would appreciate any comments:
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From one perspective, to name any technique a "master key" is missing the point. I have seen lists of what people consider THE "master key techniques". This, to me, artificially limits the concept. A master key is simply a move or sequence of moves that can be used in more than one way. Shouldn't this describe everything we do in Kenpo? Can't you use an "upward block" for multiple purposes? A block, a strike, an arm break.... Does this make the upward block THE master key block? No, because you can say the same of any block.
Surely, Five Swords can be used in multiple ways, and thus can be a master key technique. However, if you cannot apply any technique to more than one situation, then you haven't looked hard enough. So in that regard, all techniques can be master key.
To me the 'master key' concept is less about the technique or move, and more about the practitioner's understanding and perception of it and whether he can see how the technique can provide multiple solutions to different circumstances.
I think about my office key that opens everybody's door in our office building. Not everybody's key is like that. I have the master key. (Evil laugh here --MMMUUUAAAHHHHaAAAHHHAAA). But seriously if you can use Alternating Maces in multiple scenarios (such as right punch or push, left punch or push, left or right kick...) shouldn't that be called a master key?
With that said, I do believe there are "root" Kenpo techniques back to which you can trace all the other techniques in the curriculum as variations. Let's take Attacking Mace, which is "root" to the extent that it is the progenitor of the family group that includes Dance of Death, Thundering Hammers, Sleeper, Flashing Wings, Circling the Storm. In other words, the "root" technique is the first one taught of a family group in the system. In the same way, Delayed Sword would be the root technique of the family group that might include Alternating Maces, Five Swords, Calming the storm, etc. Sword and Hammer would be a root of a family including Obscure Sword, Obscure Wing, Obscure Claws, Falcons of Force, Snakes of Wisdom, etc. It is obviously better to start with a root technique that is less sophisticated, and then build upon it. (What I call "root" might be called "master key" by others.)
Related to Master Keys and Family Groups, yet different from them, is the topic of Associated Moves. This is where you can find the same or similar moves from one technique in another. Take the striking sequences in Thundering Hammers and Flashing Wings. They are very similar and associated. Not only are these techniques in the same family group (same father, different mother) but their strikes contain very similar patterns and methods of execution, though the angles of execution and weaponry and targets are different. Therefore, they use associated moves. They are related (family group) and associated (common patterns in the technique).
Similar to family groups where you have root techniquues, within associated moves you have core techniques that first introduce the common pattern, concept or principle.
That is the way I teach a new technique; I review with the student one he already knows from the same family group or one with associated moves to give him a point of reference and then I show him a variation of it which becomes the new technique I want him to learn.
At some point, honestly, the boundaries disappear and you should be able to show how any one move or sequence of moves is associated or related to any other in the system.
Just random thoughts on this topic.
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Well, that is what I wrote. I would look forward to any comments.
Derek