I am not sure if there is memory capacity or not to our brain(finger, audio, visual memory). Will we forget our previous piece that we memorized if we keep on memorizing more and more piece? About how much "length time" have you guys memorized if all the pieces you memorized are added together? I am afraid that i will lose all my old stuff if i try to memorize new stuff.
You don't forget when you remember new things. You forget because you fail to refresh your memories.You can't 'overwrite' things you remembered. Thats because of the amazing way our brain functions.
By the way, how many pieces have you can you guys memorized before you start forgetting old ones? I should rephrase the question, what are the maximum length of memorized piano pieces have you guys ever had?
If everyday, you play the pieces you want to keep in your mind so it is always ready to be performed, can you play the pieces once daily before you start to learn new stuff? That way will you be able to polish it so that you wont forget? Will that work?
When you say "once daily", do you REALLY mean playing it each day for the remainder life.If so, you probably will not feel so oblivious or forgetful of it.