IMHO, many thingies in music occur because of mistakes. A finger slip here, a twitch there can lend some interesting affects to music that were not planned. I believe that is why trills, grace notes, mordants etc. exist in classical music. Instead of recifying the blurb, the early composer would write the mistake in the music ( I meant for that to happen ). I composed a piece in college for piano and trombone. I am no pianist at all which was why I composed the piece...less chances of making a mistake. Well my finger slipped and added the 7th and/or 9th note which sounded good to me so I left it in.
Mistakes in a performance cannot be treated as mistakes. The mistake has to become part of the performance and do not share the mistake with anyone. If someone comes up to you and says "Wow, what a performance! Don't reply back with "Yeah, but I missed the g in the 5555th bar, I couldn't believe it". No matter how hard and how perfectly we practice and rehears, there most likely will be a mistake...Yo Yo Ma makes mistakes but that doesn't take away from a beautiful performance. That won't take away his "soul" in the performance.
Worrying about mistakes invokes a fearful performance. Don't be skerd. Remember Babe Ruth did not hit every freakin' ball out of the ball park. He even missed a ball or two. But with every ball he swung at, he swung with all of his might...no fear.
Oh BTW, lookie here. Can you figure out which on is me
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