About the 20 minutes methode...Bernhard
Take for instance you start learning Chopin Etude Opus 10 N° 2. You do 7 times, lets us say measue 1 to 6. Then you decides to go on for 20 minutes. Well I did. But what is the speed that I have to be at at this point ? I'm in the, what Bernhard says "the learing step". Sould it be as fast as performing speed ? Or just an easy speed. This is never mentioned before.
HELP
To answer your question:
Aim at the final speed – or if you can manage – aim at an even faster speed. What you truly want is to get to a position where the final speed
is an easy speed, and the only way to do that is to aim at a faster speed than the final one.
However, if I was starting this particular etude, I would not plunge straight in on, say, measures 1 – 6. (This is the advantage of asking specific questions: you get more useful answers).
This is what I would do (and of course you have no obligation to do it.

)
Stage 1: Outline.
1. Start by rewriting this etude (I use a notation software for this purpose which can also playback to me what I wrote – this is a huge learning resource) in the following way: Delete completely the top voice (the chromatic scales) so that all that is left in your score
is the left hand (Bass note – chord – bass note - chord) and the thirds and fourths in the right hand. I trust that just by looking at the score you will see immediately what I am getting at. In case this is obscure, the RH in the first bar would consist (in this outlined version) only of four chords: CE – EA – AD and DF.
2. Now make a separate score with the chromatic figurations only.
3. Finger, in your scores every single note with the final fingering, that is the fingering you would use when playing the etude as originally written. This is the most important instruction so far. You must from the very start use the final fingering no matter how awkward it may feel. This creates a problem. In order to figure out the final fingering you will have to play the etude as originally written. If you have a teacher (or an edition whose fingering you can trust), then there is no problem, just follow their fingering. If you are an advanced student (and if you are tackling this etude you should be), then you can pretty much figure out the fingering just by sight reading through the etude in sections. If you are a beginner however who has no idea of what I am talking about, then you are in trouble.
Anyway, as you rewrite the score and finger every single note – this is basically desk work, not piano work – put a CD of this etude played by as many pianists as you can find (over 100 pianists recorded it) and keep listening to it.
This work of rewriting the score will prove invaluable as a way to get to know this piece back to front, since not only you are rewriting it as you are “deconstructing” it. It will give you an insight on how Chopin created it (even if this is not the actual way that Chopin did it). It will pay handsomely every minute invested in it. So do not be in a hurry. As you are doing it, identify all the chords and chord progressions, mark the cadences and identify the several scales/keys used.
4. Now that you have 2 scores – one with the outline, and one with the chromatic scales, each correctly fingered, it is time to go to the piano. Start by learning the outline. This outline is very easy - around grade 1 – grade 2. You should have no problems mastering and memorising it in a couple of days – one week. The fingering may seem awkward, but stick to it, since you will be using the other fingers to play the chromatic scales later when you put it all back together again. One of the greatest advantages of learning the outline first is that you can start working on musicality straightaway. What you have in the outline is the essence of this piece. In a sense the chromatic scale is just a “filler”. So, learn the outline (and use all the tricks all have talked about: small sections, separate hands, repeated note groups and so on), and keep practising it throughout the whole process of learning this etude. The foundations of your musical playing will be laid here, at this stage.
5. Dedicate one of your practice sessions in the day to learn and work on the outline. Dedicate another session of the same day to work on the chromatic scales. Here of course is the main technical difficulty in this etude: playing chromatic figurations with fingers 3 – 4- 5. Later on you will have the second difficulty: playing chromatic figurations with fingers 3 – 4 – 5 while finger 1 – 2 are playing the right hand chords. And finally the third difficulty: to do all that at breakneck speed.
6. To sum it up: Do not start work on this etude until you can play the whole outline perfectly (and musically) and until you can (right hand only) play the complete chromatic figuration from beginning to end. A very important warning: do not work on the chromatic figurations for more than 2 – 3 minutes. You can get a nasty injury. Do 2 – 3 minutes and then spend some 5 minutes doing something else (e.g. working on the outline). Then another 2 – 3 minutes on the chromatics, and 5 minutes on something else. Why not learn the revolutionary at the same time? It follows the same principle: outline and work on the LH figurations. So you could alternate the right hand of the op. 10 / 2 with the LH of the op. 10/12. And when learning the RH chromatics, use all the tricks in the book: small sections, repeated note-groups, rhythm variations, etc.
Now you can move on to the 2nd stage.
1. I would work on this by establishing my basic unit as five semiquavers. Each bar would have five such units (the fifth semiquaver of a unit is the first semiquaver of the next – this provides overlap between units). Then I would work in groups of 7 units by repeating then in the fashion below until completely mastered:
1 Unit groups: 1 – 2 – 3 – 4 – 5 – 6 – 7 - 8
2 unit groups: 12 – 23 – 34 – 45 – 56 – 67 – 78
3 unit groups: 123 – 234 – 345 – 456 –567 - 678
4 unit groups: 1234 – 2345 – 3456 – 4567 - 5678
5 unit groups: 12345 – 23456 – 34567 - 45678
6 unit groups: 123456 – 234567 – 345678
7 unit groups: 1234567 - 2345678
the full section: 12345678 (that covers two bars plus the first beat of the 3rd bar)
The reason for choosing 8 units is simply one of time/fatigue. Anything larger than 10 units and it will take you the full day to complete the cycle. When you do this sort of work you cannot stop in the middle: all your work will be wasted if you do. So make sure that once you start repeated note-groups you finish it. The routine above will take up to 45 minutes to complete. But depending of your level you may finish it in much less time. Some units may be far more difficult than others so you will need to spend more time on them before moving on.
Once you can do the full section, do rhythm variations (particularly useful in this kind of passage).
You can go for it hands together straight away since you have already done your hands separate work when you worked at the outline and at the chromatics isolatedly. Also do not worry about musicality for such small sections. You have already worked on it when you did the outline, and it will percolate to this practice without you even being aware of it. For the moment concentrate solely on technical issues (getting the right notes at the right times, getting the correct fingering thoroughly ingrained so you can do it without thinking about it, getting the correct movements so that appropriate notes get accented automatically, getting the notes at full speed, etc.) If you do this consciensciously and with full awareness, you will be surprised how much musicality you will get without aiming at it at all. Later on when you have larger passages to work on, then you can start working on musicality.
Divide the etude in two bar practice sessions and repeat the above for every two bar section. Do it like this:
Session 1 – Bars 1 – 2 (add 1st beat of bar 3)
Session 2 – Bars 3 – 4 (add 1st beat of bar 5)
Session 3 – Bars 1- 4 (add 1st beat of bar 5
Session 4 – Bars 5 – 6 (add first beat of bar 7)
Session 5 – Bar 1 – 6 (add first beat of bar 7)
Etc.
As you can see, every other session is dedicated to joining small sections, so you are always working in the previous sessions. It is in these larger practice sessions that you can really start working on musicality.
Now, the scheme above is just a suggestion. I don’t know you, so I cannot really tailor it perfectly. If you think you can deal with more bars per session, by all means do. If you cannot deal with two bars per session, do just one, or even half a bar. It may take longer, but you will get there.
Finally, have a look at Cortot’s “Edition de Travail” for the Etudes, he has some excellent preliminary exercises you can use concurrently with the learning of this piece.
Best wishes,
Bernhard.