At risk of disappointing you, I have some real questions as to whether this makes very good sense.Jeremy, difficult FOR WHOM? That's where it stops working, I think.Because different of us pianists here, amateur or more, have different kinds of skill. What is a struggle for one piano student may be a piece of cake for another.I will take on almost any piece, perhaps not wisely, but I very much dislike very fast runs. Perhaps due to the fact that I'm a senior citizen. Although, in truth, I never did that well on extremely fast runs even when younger. I tend to avoid those pieces. But, in compensation, I have strengths as well. This is going to be true of most of us.In other words, the variable here would be the individual piano student. And how about hand size? I play pieces with tenth intervals throughout. Wouldn't a woman or a young pianist with small hands have considerable difficulty with these pieces? Again, the variable is the human performer.And, on a different tack entirely, I also become very weary of this continual obsession here -- by quite a few posters -- to rate lists of pieces for difficulty.Do you suppose this follows the "Boy Scout merit badge" school of performance?In other words, "I can out-boast you because I can play "piece X," and you can only play "piece Y." And you can see from the posting of the esteemed Dr. Expert that "X" is 0.2 percent harder than "Y."Somehow we are all trying to score points off of each other, and no one seems to care very much about the musicality of the respective pieces.It is all very simple. Study the material and try to play a few bars. If it is too difficult for you, lay it aside. We don't need an Einstein to tell us that. Have a good one --