I agree with Scott...when I learn a new tune, I go over it once or twice and write the lead line, changes and words out on a reference card. I try to destroy the card in a week, because, if I don't force myself to play by ear, that card will be yellow and falling apart years later...I'll alway rely on it and never really "learn" it.

At the same time, preparing for studio sessions or playing requests I don't know is much easier with the sheet in front of me.

Both are important!

Russ