Music literacy (numeracy?) is just a skill. If you have it you are not automatically a 'better' musician. But it helps you become one. And it enables anyone trying to advise you to do so in more precise terms.

I agree countess - I hope I didn't give the impression that I thought I was a 'better' musician for seemingly having an ability that not everyone has. I know several better musicians than me, who seem to struggle if they don't have the music in front of them. But as musicians, they're better players than me. I couldn't do what they do any more than they could do what I do.

If you play in an orchestra, the ability to play without the music, or to follow a tune and accompany it, doesn't matter because this ability isn't required. It's more important to be able to play your instrument well, and play it as written (OK, that's an over-simplification, I know there's more to it than that!)

But for someone like me, playing in folk clubs or folk bands, the skill is very useful, and I would certainly find it more difficult without it.