True, but my understanding is that very, very few students do this. It isn’t really encouraged much.
I will say that I don’t think Yale is necessarily the best place for somebody looking at a musical performance career. There is no performance track in the music major, and the environment isn’t really conducive to somebody who wants to spend most of his or her time focusing on practicing and performance. For composers (like my son), I think it’s really excellent, as well as for people interested in music theory, etc. For non-majors who are serious about music, it’s really terrific.