Today was one of those magic days when an experiment comes out better than any imaginable hypothesis.
Two young people have been learning together four-hand Stravinsky pieces which I do not know. It's fair to point out how much I enjoy teaching music I don't know. Sounds like an oxymoron. But in listening as the students learn I learn to hear as they hear. The questions that arise are deeply artistic and are clearly audible to me in the playing.
Today I asked them if they could imagine why I do not insist that they practice their separate parts at home. "If we did," said one, "we would form an idea of how our part goes without the other part. Then, when we played together, we would not listen to the other part." (The emphasis is mine.)
She articulated exactly what I try to tell people learning chamber music: don't practice your part because you will form an entirely false idea of the music and you will not enjoy the total sound made when all the players are together.