I agree with what you are saying. I also think there is another half of it - I would like to read something by someone who has at least a vague ability to guess what is going to be obvious to me and what is not. It's kind of the difference between a teacher and someone who knows things - I want someone who not only thinks, but who has thought about how they think, and about how I might think.

For instance, I grew up in a household full of singers, and I have never had trouble singing harmony, and I don't go off pitch. When someone can't sing without changing keys every phrase, I can't tell them how not to do that, and I can't tell them how to hear when they are flat, or how to phrase a line, because these are simply things I do. I am therefore the wrong person to talk to if you're trying to learn how to sing.