It's sounds funny, but I remember the same thing happening with math. Let me explain...Right after high school I started working at Santa Clara Elementary School District as a Computer Coordinator. I developed and implemented the computer curriculum and designed and setup the computer lab. I also taught Computer Literacy to students in grades 1 through 3 and taught Computer Programming to students in grades 4 through 6. During the first couple of hours of the day I would work as a Teacher's Aide helping students with their regular class work.
I first noticed that I had been skipping a lot of steps in math by using shortcuts, when a student needed me to explain how to multiply. I thought to myself, that's a very good question. How do you multiply? When I multiplied, the whole multiplication table was in my head, but how do you EXPLAIN multiplication? Then it hit me, SETS! With that bit of basic knowledge recovered from the unused portion of my brain, I was able to explain it. 3x4=, You have 3 sets (or groups) with 4 blocks (sticks, apples, whatever) in each set. I had forgotten the basics.
Same thing happened with music, I started to just play the music and forgot the basics. I would look at a note on the music staff and just play it, my fingers just knew where to go. If I had to figure out what the name of the note actually was, I would have to count up or down from a known note to find it. I realized this when I tried to sit down at the piano after playing the clarinet for many years. I knew how to play the piano by the name of the notes. My fingers didn't automatically know where to go, because I didn't play the piano that much. I had forgotten the basics.
I now feel very good about being in this class. I am where I need to be. The class is not a going to be a piece of cake, but I will have an easier time, since I had this information at least once before. The one new thing that I've never done before is composing. We are required to compose something for our final project. Since this is an accelerated summer class of 4 weeks, I don't think we will be producing a masterpiece. Then again, I might surprise myself. hehe