I recently received an email that read something like this. Not long ago I read something about how you learned to practice the vibraharp in your mind when you didn’t have access to the actual instrument. I think you called it ‘virtual rehearsal.’ At first I thought this idea was ridiculous. (You don’t even want to know a few of the comments I made.) Well, I’ve since changed my mind. I teach piano and two of my little students have no piano in their home. They are able to practice on their grandmother’s piano—but not every day. I decided to give this idea a try. I mean, it couldn’t hurt, right? Although I was not sure it could help, either. I told these little piano students to practice at home in their minds (with their open music books) on the days when they are unable to practice on their grandmother's piano. They were, of course, almost as astounded by this instruction as I was by the concept. Guess what has happened? They have discovered that “virtual rehearsal” works and are making progress by leaps and bounds. Naturally, I am so pleased . . . and grateful. You also said once that “What you don’t know you don’t even know can limit your options and sometimes cause you a great deal of trouble.” This ‘virtual rehearsal’ experience was a great object lesson to me and has encouraged me to be more open minded. Again, as you said, “No one can know everything.” What do you think made my brain so ready to brush off this information?." My response tomorrow.