I guess I have a lot to ay about this. My first musical learning experiences were on the banjo using The Murphy Method as taught by Murphy Henry. Her whole premise is that you can learn entirely by ear. Well, I found that I learned a lot of her stuff note for note, but I had no idea how to improvise or jam. I then took some lessons where I learned to read tab and got some basic theory. I have stopped taking lessons because it was too technical. I think that a banjo is very much a "feel" instrument and that although a bit of theory can be helpful (e.g. transposing) it is over-rated when it comes to banjo playing. Besides, I have a top notch banjo player who is willing to help me if I can just make it in to Toronto on his schedule.