**** the most important element in music, which is musical time out of metronomical or measured time, ****
That’s right. I would qualify that comment by streamlining the idea even further to simply “time”. Time is the most important element of music; and not only time outside a metronomic reference. It has to be all inclusive as far as possibilities. There are times in a musical performance of a particular work when metronomic time is precisely what the music demands; whether it be specified in the score, or whether it is an aspect of a conductor’s vision for the work. It is the musical cohesion and logic between the two polarities (to use your word) and all points in between that make a great performance. It is true that in Jazz this idea is “at the heart of what improvising musicians (do)”, In a much more subtle and much more controlled way it is the same and essential for the written score. In orchestral music, the magic happens when there is agreement with, or at least respect, for the conductor’s concept. That Bernstein/Corialan is a great example. Not only is it clearly heard, one can see the agreement and enthusiasm in the players’ body language, No matter the level of professionalism on the part of the players, there is always a bit extra given when they “get” what the conductor is trying to say; or, agree that the conductor is allowing what the composer is trying to say to be expressed. This is not always the case. In a way, the same thing happens in Jazz.

