Be sure to catch this post from the Greenleaf Music blog. Dave Douglas has so much to say both musically and verbally. It's damn cool to read his ideas on the relationship between composition and improvisation and the art of meshing both. His thought process explains why his music has such a strong attraction for me. The thing that made his work with his groups New and Used or Parallel Worlds so compelling was the seamless combinations of through-composed and improvisational textures. The quality and style of the performers in those groups had a lot to do with the success of this approach as they meshed so well aesthetically with Douglas's compositions. It's something that he's achieved so consistently with so many different groups. I'm anxious to hear this chamber concerto he's working on.
One of the best groups I heard in Toronto from my student days was the Hemispheres Orchestra. This was a large ensemble that really struggled - and often succeeded - to mesh the through-composed classical with improvisation. They did this by commissioning works by people from both the jazz and classical communities in Toronto. (And it was often remarked that the "jazz" people were very good at getting their work in on a deadline and the "classical" folks were consistently late.) "Butch" Morris came up and did a conduction with them and some of the works I heard them perform seemed to break new ground for group improvisation. But the best works were the one that managed to blur between the written-out and the improvised materials so that it wasn't always audibly clear which was which. For a holiday season treat they would play the Billy Strayhorn arrangement of the Nutcracker Suite and they really let it swing.