Giddins and DeVeaux on Miles Davis

"In the year between Porgy and Bess and Sketches of Spain, Davis regrouped his sextet to record a few unrehearsed musical ideas that he had been toying with and soon released as Kind of Blue. This album represented the fruition of the modal approach he had been working on since the film scoring in Paris, and would alter the playing habits of countless musicians. Here, in contrast to the strenuous orchestral projects with [Gil] Evans, Davis kept the compositional demands minimal. Determined to stimulate each of his musicians, he did not show them the pieces until they arrived at the recording sessions. His goal was nothing less than to banish the clichés of modern jazz. By 1959, jazz had been fixated for fifteen years on chromatic harmony and the technical challenge of improvising smoothly and efficiently within it. The liberating innovations of Charlie Parker now loomed as an unavoidable and endlessly imitated model. … In his early years, Davis had tried to prove himself precisely in that manner. But modal jazz sent him in the opposite direction: fewer chords and less concentrated harmonies — or rather, scales that override harmonies" (Gary Giddins and Scott DeVeaux, Jazz, p. 418).