I think the discussion came from a post about hearing a song and playing the chords. Some of the replies, including mine, talked about playing experience and ear training. Those are not the same as reading music or sight reading (also different, as Bob said).

If you are going to play an instrument or sing complex music, it is much easier if you at least understand scale degrees.

One thing I have noticed is that some musicians who are great readers don't improvise well.

I don't think anyone said a musician is crippled by not being able to read. At the same time, more ideas and opportunities are open to you if you can.

2b

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