Yes, it is a great masterwork. The vision of your teacher is certainly right. Its architecture seems both very free and quite firmly design.From a strictly technical point of view, it took me some time to understand how reading the intrication of soloist and orchestral parts, including of course the part of determinism and free choice. This question is even more coplex with such composes as Boulez or, in a quite different style, G. Crumb , who sadly just passed away.
A great piece. I remember listening to a live broadcast the premiere in London and being enormously impressed and my admiration for it has grown ever since.
At the time, it was the only recording I had actually listened to, I still think its amazing though (esp for being live, and the orchestra sounds a lot better here imo than other competition orchs) so I don’t regret it
