The greatness of Mac Rebennack, alias, Dr. John, also known as John Crieux, rests on his command of the musical use of idiomatic expression. Not a technically well-endowed singer, nor a great songwriter, he leaves his mark through the discipline and control he exerts over all that he touches.

Since her landmark 'Tapestry,' Carole King has both oversimplified and over elaborated that masterful album's style until her music has become something more overtly but less effectively personal.

Elton John can be a master of the sleight of hand. The arrangements make it seem like there are substantial melodies underneath the tracks - but almost nothing demands repeated listenings. Similarly, he always sounds like he's singing up a storm, but his voice glosses over the material, reducing most things to an uninteresting sameness.

There is something complete about Stevie Wonder, and one senses that he is not only exceptionally important today, but will continue to be for as long as he chooses.

Everyone eventually winds up writing about themselves - the problem is finding the best way to go about it. To write about oneself literally, in the first person, presumes a more interesting personal life and philosophy than most rock lyricists possess. John Lennon was good for one great album based on musical direct address, 'Plastic Ono Band.

The Stones were always exemplary of one of the best of all rock qualities: tightness. They have always been economical, the opposite of ornamental. Having a very clear idea of what they wanted to say they could go into a studio and make it all up on a three minute cut.

On first listening, Joni Mitchell's 'Court And Spark,' the first truly great pop album of 1974, sounds surprisingly light; by the third or fourth listening, it reveals its underlying tensions.