Interpretation is as improvisation as improvising from silence is. It is just a different way of looking at it. When you improvise form interpretation you have certain dramatic ideas, you have a certain structure. But you know that everything that is in that is relative and flexible. Even pitch can be a matter of interpretation. Rhythm is relative.
I’m kind of at the point where I’m doing the second of those things and surprised by what I have done. And it is not necessarily a big master plan, but I look at the number of recordings I’ve made and I’m kind of shocked.
It is not like we have a piece written out that we improvise on. We know where we are going but we don’t know how we are going to get there.