The rules of music and the rules of kung fu are very closely related. For instance, one of the most important aspects in music is that of tempo and rhythm melody. In martial arts these concepts are also very important, however, in martial systems these element are so frequently unexplored that most are completely oblivious to them, or know very little about them. That is, while many can execute the lessons and forms passed down by Chan Siu Duk (Jimmy H. Woo), they cannot tell you what the timing and rhythm of each technique is.
Degeneration
Because of this, many have change the rhythm of the melody (so to speak), so drastically that without even knowing it, they're doing their version of the technique, thinking it perfect. Once this change has occurs, then the original lesson or form, will no longer exist after one or two generations. Even if one continues to do the movements correctly, the essence of the technique will no long be there. Why? Because in the very same way that each and every musical note must have its own proper tempo and rhythm melody to convey a particular song, so to must each individual kung fu movement, and if it does not, the technique like a musical piece will break down, and degenerate into something else. Now, sometimes one can do their version of a technique without proper timing and rhythm, and it might work, especially in the studio where it will look great, but on the street, in a real combat situation, your chances of success will be 50/50 or less.
Exploring Rhythm
To find out what proper rhythm and tempo is in the martial arts, let go back to the theme of music. Just tap out the song "happy birthday to you" with your fingers on top of your desk. This will give you your rhythm (flow), and tempo (duration or speed) of the piece your playing (executing). So, knowing the proper flow and speed of this piece gives you a happy tune. However, using the very same words and notes, but with a different flow and speed you will have a radically different tune. It may become more hip like rockin and roll, or it might become the blues, and it may sound good, but its not the original song. So, if one plays the song (executes his techniques) incorrectly, by holding or speeding up any one or more of the beats, it will change, and destroy the original song (fighting technique) making it almost unrecognizable, even though you maybe using the correct words or notes (hand or foot moves in kung fu terms). So, if you do not know a songs rhythm melody and tempo you may end up playing a rockin and roll song as a polka, which just won't work.
I remember in the old days students coming up to Jimmy days or even weeks after he had taught a particular lesson or form saying "I'm having trouble with this can you help me", then they would demonstrate it for him. Jimmy would just shake his head No, and say, "I didn't show that". Because they were showing him their version which had already degenerated into something else.
So, I hope my readers can see that each and every fighting technique has its own tempo and rhythm, and changing it, can have disastrous effects even if everything else in a lesson remains the same.