Having good memory is important. It seems to me you have a really good muscle memory and that has helped you play without looking at the score. I've played the

Having good memory is important. It seems to me you have a really good muscle memory and that has helped you play without looking at the score. I've played the piano since a very young age and the thing is, learning to play without looking at the keys (eg whilst reading) is actually a good skill to have. The argument goes that this way you can look at one hand without worrying about missing with the other while in a concert. I tend to agree. Also I scribble a lot in my sheet music because part of studying a piece is discovering things written in it (everything has a purpose, every staccato, forte, piano, etc.)