I have been working on a piece that was stretching for me and was told to put it on the back burner and come back to it. It was then replaced with an even harder piece.

I let the teacher know that the new piece was probably going to be even more challenging than this last one.

Im not asking whether its right or not to do that, but under what circumstances would you do that or what are you trying to teach or pull out of the student?

Im probably over thinking this...

I just asked a co worker of mine and I think his answer is the best:

"I think he does want to challenge you w/ a harder piece to try to get you to the next level but didn't want to bogg you down w/ Chopin which you already hit the wall on. A new piece with new (but different) challenges may help you get through the Chopin wall."

Brilliant!

If you can play the Chopin 25/2 etude,
you're right up there and are capable of
tackling anything. So this doesn't
sound unusual. With a player at
your level, the teacher can do
all manner of things without
any problem.

Just an observation on your repertoire. It seems to range from middle intermediate to upper advanced. That's rather peculiar. It spans what most students do in middle or early high school to advanced college work. I'd quiz my teacher on this a bit.

The pieces I was referring to was putting away the Chopin( I can play it by memory and for the most part up to speed but I still fumble when I have to perform it infront of him, but he is wanting it to be more clear and less glossed over with a certain finger technique) and picking up the Mozskowski.

As for my variety of pieces, I started playing when I was 16 (Im 31 now), after 3 yrs of middle school band (trumpet). I didnt really learn any easy pieces as I stared with a chopin nocturn, self taught over an entire summer. So I think we are going back to relearn refined touch and musicality through technique with the easier pieces, even though I took 3 yrs from professionals (Ph.D's from Stanford and UNT in piano performance etc...) who I guess felt I was up to the challenge of more technically demanding pieces.

I stopped playing while in college briefly taking a semester of piano (did the chopin grand polonaise) Ive always been able "figure out" harder pieces. I love my current teacher of 6 months because he hounds me on all my bad techniques and takes the time to explain why I should be doing things in a certain way so that I can retain it.

I hope that may answer some of the riddle to why I have a mixed bag of pieces Im working on.

Chopin Op. 10#1 uses a very specific type of technique.

I seriously doubt the new piece is simply "harder," it probably has a different set of challenges.