I never had a good relationship to fusion when fusion was most popular--a period that coincided with my own teenage years. Now I can appreciate certain aspects of it more because I no longer feel resentful that it watered down jazz just at the moment when I was coming of age as a jazz fan. I remember going to a Hubert Laws concert in college and being very disappointed by the absence of improvisation and the willingness of the audience to applaud the merely familiar, the exact riffs off the records. To understand fusion, I think we have to think of it as one of the four main movements in jazz between bop and the neo-classicism of Wynton Marsalis in the 1980s. Remember that Wynton began his career reacting against fusion (and free jazz to a lesser extent) and reviving hard bop. Let's look at these four movements, more or less in chronological order:
Cool jazz: Key figures: Miles Davis, Gil Evans, Lennie Tristano and his school, Bill Evans, Gerry Mulligan, saxophonists influenced by Lester Young.
Relation to popular music, culture / hybridity: This movement had its moments of greatest popularity in the success of Dave Brubeck, Chet Baker, and Stan Getz. It represents the fusion of "white" and "black" forms of jazz in an experimental context. It can be seen as both cerebral or as quasi-popular.
Hard bop: Key figures: Art Blakey, Horace Silver, Max Roach and Clifford Brown group, Miles Davis, Cannonball Adderley. Other Blue Note artists.
Relation to popular music and culture / hybridity: Fusion of jazz with gospel and R&B.
Free jazz: Key figures: Ornette Coleman, John Coltrane, Cecil Taylor, etc...
Relation to popular music and culture / hybridity: intersection with Afro-centrism and the black arts movement; popularity of Coltrane. Ornette's use of electronic, fusion oriented bands. Beginnings of "world music."
Fusion: Key Figures: Miles Davis, Wayne Shorter, Chick Corea--many other alumni of Miles's bands... Chuck Mangione
Relation to popular music and culture / hybridity: the entire style was based on a fusion with certain elements of rock, especially in terms of rhythm and use of electronic instruments. Collaboration between black, Latino, and white musicians is the norm.
These brief descriptions suggest several conclusions:
*** The interaction of jazz with popular music is a constant, present in all four movements. The bluesiness of hard bop should not be seen as alien to the funkiness of fusion. Think of Joe Zawinul's hit "Mercy, Mercy," which he wrote for Cannonball, and his later hit "Birdland," which he wrote for Weather Report.
*** Jazz is always a hybrid music, always responsive to other styles of music.
*** Miles Davis was heavily involved in just about everything during this period (1950s-70s), except for free jazz. Of course, there are freer influences in Miles's music too, especially in collaborations with Wayne Shorter. Many musicians of the period crossed boundaries among these four styles, though none as much as Miles. We've got to see them as overlapping both in time and in terms of the musicians involved.
*** The neoclassical revival of the 80s chose ONE out of four interesting developments of the preceding period to champion. Jazz-rock fusion and cool jazz were too "white," or too hybridized, for Wynton's taste. You get people like Crouch saying that Bill Evans couldn't swing or play the blues.