In my opinion, the beauty of an album like Kind of Blue, and that genre of expressive jazz, is the ability of the musicians to "lock" onto a flow that they all have in their minds. They are all improvising, yet they seem to know where each other is going, and where the music is going. It is an ethereal thing. Like all of them have "tuned in" to a wave, and are riding it with their improvisations. No matter what timing changes, or modes or rhythms that they move through, they don't "lose" each other. Many other jazz attempts at this result in gibberish. Alot of live jazz is done in an attempt at finding this "meshing" and sometimes it is successful, and sometimes not. When it happens, it is magic. This is a good example of what Kind of Blue is. It is the connection of the musicians on a different dimensional plane, expressed through the musical improvisations. Many improvisational musicians know that sometimes the music just flows out, without even thinking. It comes from somewhere else. When all the musicians are flowing from the same connected "somewhere else", music is created that is beyond the musicians themselves. That is the only way I know how to describe this.