This is really a very interesting thread! I memorize pieces for solo performance, and sight read (duo, or whatever) ensemble pieces. I find that memorization actually gives me much more freedom in interpretation, from one performance to the next. I memorize the notes, not the way I play them. The guitar repertoire is as vast as that of the lute; it's not like we have to just learn a few "masterpieces" and then begin our world tours. For the audience, I think concerts are like "theatre". To sit down and play with nothing between you and them but your instrument, probably seems a bit magical. Imagine going to a production of Shakespeare, or an opera, and having the cast walk out with notebooks to recite their lines from, or remind them of the lyrics...
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