Tab or staff notation, very useful as a back up to playing by ear. But it's a terrible shame when people get to depend on having the notes written down somewhere before they dare play music. I've sat with people who can play their instruments far far better than I can - and they're paralysed because they haven't got the music written down.

Tab is different since generally it's used as a learning tool rather than in real time playing; but if you don't feel free to try playing something without having permission in writing it's just as bad. The people who gave us this music wouldn't have understood that kind of attitude.