And I'm another classically trained musician. Started on piano when I was a kid, and ended up studying voice in college. I was lucky, in addition to the usual voice repertoire Der Erlkönig by Schubert, selections from Handel's Messiah my voice teacher encouraged me in my interests in both traditional and contemporary folk music. In fact, my senior recital was a combination of original songs, and traditional Appalachian folk songs.

I have heard it said, and it has been alleged in my presence that classically trained vocalists can't yodel. I am here to prove that statement incorrect. I haven't gotten any grief from classical or folk singers so far. And to my utter surprise, audiences seem to enjoy my singing. It seems all too easy. I must be doing something wrong. ;-)

I agree whole heartedly that learning to read music is a valuable skill to have in one's musical tool kit. I have learned a few arcane fiddle tunes because some one like R. P. Christesen wrote them down and put them in books. Some of these tunes have never or seldom been recorded. There are likely other fiddle or song collections out there that are the same as The Missouri Old Time Fiddler's Repertoiry, containing little known pieces that are worth exploring. But if you can't read music, you'll never find 'em.
Jim