Not sure if a degree in music is intrinsically of any use whatsoever to PERFORM music. You can have one and still not be a good musician. Regarding the TEACHING of music, it all depends. The best traditional musicians often have learned from other great traditional musicians and this has continued for centuries without a degree anywhere along the line. Also without reference to music thoery or sheet music.

There's no way I can agree with the above statement on sheet music, "...they can all play straight off sheet music. That is how it should be. Anything less damages our culture" Who's culture?

If I were choosing a teacher I'd want to (a) hear them play, (b) see them teach and possibly (c) hear their pupils play. I wouldn't necessarily rule out hiring someone who had played guitar in 5 rock bands over the last 10 years, without a formal qualification.