Well, like that poet, composers of the Great American Songbook are allfor lack of a better worddead. And jazz artists happen to be a highly reverential lot. Each performance of a "standard" is, in fact, a musical eulogy. The musicians start with a solemn reading, interpreting the dead composer's melody, sticking respectfully close to it. Then they improvise, spinning original lines within the dead composer's form and harmony. This "insanity," as you call it, is actually the jazz artists' genius, and there could be no deeper, more heartfelt testimonial to the dead composer. Some jazz musicians are so moved by the dead composer's death that they solo for twenty minutes or longer, screeching and honking with animal noises from deep within, channeling the bereft widow's heart-wrenching wail as the dead composer's casket was lowered into the earth many years ago.
Once the outpouring is complete and catharsis achieved, the artists then conclude, more soberly, with a restatement of the dead composer's melody; a final heartfelt tribute. It's all really very simple, if a bit morbid.
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