hardest piano piece i've ever played

Here by hardest I mean mechanical difficulty, not separable with musical difficulty though.
Mechanical difficulty, in my definition here for this blog's sake, is expressed in terms of the time it takes to be able to simply press the keys at a reasonable tempo, and does not mean at the level you are fully comfortable with the playing the piece beautifully in public.
The time it takes to reach that level is decomposed into (i.e. sum of) (1) the time it takes to read the score, and (2) the time it takes to overcome mechanical flaws.
One of the hardest pieces I have ever spent time on is Lavapies from Iberia by Albeniz, whose difficulty is mostly attributed to (1), like other pieces I tried such as 10th gaze by Messiaen.
The other of those, contrasting to Lavapies, is the 1st movement of the piano concerto No.2 by Prokofieff, on which I spent more time on (2).
The piece that I just started considering playing in the next big public performance opportunity is "Reminiscences de Don Juan" by Liszt, which I am going to apply the same strategy and tactics in conquering mechanical difficulties, i.e. rigorous decomposition of the piece into parts, prioritizing them by difficulty setting target # of repetitions, and integrating the parts into whole once I overcome mechanical flaws. By rough estimate, as I played it only a few times so far, is to take at least cumulative 30 hours of practice to give it a shape, and another 30 hours to get it the level I can play it in public, and another 10 hours to bring it to the next stage, i.e. to be competitive in competitions.

Spare 5 mins every day for planning practice

As with most, or probably all, or non-professional pianists, it must be a common issue to find time for, and to make most of, i.e. make it most effective and efficient, practice time.
For that purpose, I make it a rule to spare at least five minutes to plan the practice for the day, often write down the most critical points to focus on, and/or issues to overcome, many of which are small details, e.g. try alternative fingerings for bars xx to xx for a particular piece.
When it comes to piano, as with many other pursuits, progress should be very slow. Therefore it is important to make steady progress each day of practice, however small it may be. Making the focal points clear is meant to ensure that small progress.
I also have a checklist consisting of approximately 100 items to check if I play right at any time, ranging from hand forms, breathing, posture to "sound landscape" in my brain. Since there are so many to think about and do right simultaneously, it requires patience and intelligence to make them "natural" to me, oftentimes requiring me to "unlearn" old bad habits, which is more challenging than learning new things.
One of the biggest "old bad habits" that I have come to unlearn just recently is to flex my wrists and forearms, learning at the same time to concentrate my full attention to fingertips placing them closer to the keys.

pondering on legato, legatissimo, and non legato

I thought it's worthwhile giving it much thought about what is otherwise taken lightly but should not be.
Given the structure and principles of piano as an instrument, legato is something requires not only good control of fingers and wrists (and for that matter arms), but also good coordination and feedback with listeninng to the sounde created.
If you want good legato (bad legato means uncontrolled non legato or contaminated sound with overwrapped notes), you need to keep you wrists calm (not fixed but flexible though), keep your fingertips as close as possible to the keys, and keep keys pressed as long as just enough so that two consecutive notes sound connected to each other. This "just enough" is easier said than done. Never too short, never too long. It's a split second difference. The difference would be much smaller when it comes to legatissimo. The same thing holds for non legato. It is hard to describe it quantitatively. We need to learn by doing, i.e., playing and listening, and listening and playing.

Practice note-Los Requiebros

1. Goal: continuity or smooth transition of motif development thru variations
2. Issues to overcome: logical construction of liberal organization of the piece; expansion between fingers with flexibility without compromising beauty of notes
3. Practice tips:
* bias on left hand esp. for leading the music flow
* volume balance among voices

Basic Principles in Pianoforte Playing

Not until just recently, I found the great value of the work by Josef Lhevinne, "Basic Principles of Pianoforte Playing".
Not only the author is an outstanding performer and instructor, and not only for its thoroughness yet conciseness, but also the insights that are unique and tested over time, and above all, the delivery of the thoughts I found very creative and effective.
If we practice these thoughts in their true intended meanings to the fullest, no doubt our performances will reach the height where we performers and the audience as well could truly appreciate the art of piano playing.
Key thoughts that I particularly found valuable are:

1. What "touch" is to loosen all but absolutely necessary muscles to enable the most artistics fingertips to work themselves, without any obstacles or hitches, to create the beauty of sounds.
2. The "touch" is not to strike or drop the fingertips on the keys but to capture the keys.
3. Tha last note of a passage should be paid careful attention so that the passsage ends delicately, with a reversed (at the beginning of the passage), smooth motion.
4. The left hand dexterity is the one distinguishes the great performance from the mediocre ones. It should not be a drag. Thus, you should be able to play the left hand part solidly and independently with equal mastery with the right hand part.
5. Stop for a while to look back on your performance and think carefully if you have something to express, assert, and deliver to the audience.

Practice note - Granados, Los Requiebros from Goyescas

1. Goal: outburst of passion voiced in well-controlled and structured manner with ever-changing harmony
2. Issues to overcome: flexible and controlled left hand with flexible thumb for melody line in tenor en dehors; virtuosic passgaes by the right hand balanced in harmony with the left hand
3. Practice tips: separate voices; eight bars at a time, very slowly and carefully repeat until played comfortably

your body is part of instrument

A few days ago it occurred to me that, I could play the piano more easily and beautifully at the same time if I focused my feel mind on feeling my entire body transformed into a part of instrument, not peripheral but critical one, close to it being assimilated into the sounds I created. Having thought about the whys, it greatly helped listening to the sounds while relaxing the muscles that should not be tense, the very basics of instrument playing, or music performance. Need to hone this sense in order to achieve ever better coordination of the whole employed.

competition evaluation criteria

PTNA, national piano teachers' association of Japan, clearly provides the evaluation criteria for annual competition on its evaluation sheet, as 12 viewpoints below:

1. accurate touch
2. beautiful tones
3. precise rhythm and beat
4. appropriate tempo
5. balance of melodies and accompaniments
6. memorization
7: range and changes in dynamics
8. emotional expression
9. construction
10. pedalling
11. concentration on the stage
12. appropriate stage manner

scales, scales, scales

Great piano instructors unanimously emphasized the importance (and its underestimate by pianists and would-be pianists) of practicing scales on daily basis.
There are literally thousands of ways we practice scales.
First and foremost, there are 24 tonalities. To multiply, there other parameters as:
Upward or downward;
Unison or Inverse unison (is there such an expression?);
Both hands, left hand only, right hand only (this is actually very much effective);
In terms of harmonics, there are 8th, 6th, and 3rd;
Touch, i.e. legato, non-legato, portamente, staccato;
Intensity, pp, p, mp, mf, f, ff;
Rhythm, i.e. dotted or not among others (there are other variations);
Simply multiplied, how many are they? ... 24 x 2 x 2 x 3 x 3 x 4 x 6 x 2 = 41,472 combinations. Oops. No surprise we should spend much more time on scales.
I omitted the tempo as one of the parameters because we should normally play slowly, valuing every note carefully listening to it.

Practice note - Albeniz, El Albaicin from Ibaria Vol.3

1. Goal: controlled expression of passion wrapped mystically
2. Issues to overcome: distinguish different colors and touches; balance of left hand and right hand parts; smooth handover between left hand and right hand to clearly embosses the melody line
3. Practice tips:
・right fingering with wrist rotation effectively employed
・acrobatic mechanic in controlled and restrained intensity
4. Recommended recordings: Larrocha, Okada, Fukuma

Practice note - Beethoven, op.111, 1st mov.

1. Goal: utmost energy with outburst of unrestrained emotions
2. Issues to overcome: energetic, not mechanical, passages of 16th and the dynamic range exploited
3. Practice tips:
* fingering should be devised for expression, not ease of playing, prioritized
* subject motive clearly stand out with rapid streams of passages in background
4. Recommended recordings: Arrau, Brendel, Yukiko Tanaka, Kempf

Practice note－Haydn, Hob:XIV-52, 1st

1. Goal: amalgamation of grandiosity and delicacy
2. Issues to overcome: clear yet deep tones of harminies and evenness and leggiero of passages in 32th 3. Practice tips:
* utmost flexibility of wrists to grasp harmonics
* play rapid passages in continuum, chunks
4. Recommended recording: Kissin in London (live)

Deadly sin is the wrong notes

Definition of "wrong notes": simply creating the note that is different from what is supposed to be the "right note". Narrowly defined, it means only about the key, but broadly defined, it would encompass intensity and tone or tonal quality.
Because each note (or tone in broad sense) is an indispensable component of musical performance, the wrong note is in every sense the things that should be avoided first and foremost, and failing to do that is the deadliest sin of all.

In order to avoid wrong notes, we must first nail down their causes. They are:
1. the performer does not have a clear understanding and thus picture of the right note
2. the performer fails to pay attention to every note
3. the performer left it to chance whether his or her touch would create the right note or not (probabilstic or gamble-like playing, I dare call it)

Countermeasures woule be:
1. full grasp of the positioning and meaning of each as a vital component of the whole through rigorous analyses and imaginations
2. on top of 1., pay particular attention in parctice and public performance as well to the priority notes and those who tend to lose attention by the performer. It requires not only concentration but also the flexibility and independence of all fingers so that the preceding finger motion does not constrain the suceeding motion and other physical aspects as well. Fundamentals of scales and arpeggios are indispensable to automate the group of notes played correctly through persistent and stedy practice would help this dimension a lot
3. in particular for those notes in sequence that require travelling distance, correct use of arms and body would also be needed in a coordinated way, let alone the travel needs to be the one with shortest distance without any abrupt and discontinuous motion, and placing the fingers just a split second before they touch the keys

... not every one of them is easier said than done, but the whole boils down to creating the beauty of sounds and any aspiring pianist, amateurs and professionals alike, should pursue them at all cost.

Practice note - Schumann, Toccata Op.7

1. Goal: express the drive with unceasing motions in polyphonic harmony
2. Issue to overcome;
- balance of intensity between different voices
- changes in colors due to harmonic movements
3. Practice tips:
- flexibility of wrists in octaves, ninth, and tenth
- right fingering that enables smooth movements
4. Recommended recordings: S. Richter, M. Stadtfeld

Practice note - J.S.Bach, WTC II-22

1. Goal: express solemnness and grandiose scale exploiting counterpoint potential in modern piano
2. Issues to overcome: control delicate touch as required at the right point
3. Practice tips:
- pursue finger pedalling proficiency
- pursue stereophonic harmony with full understanding of motives and their development

Practice note - Debussy, Etude #2 "for thirds"

1. Goal: diverse faces of flowing water gently and rather wildly at times
2. Issues to overcome: smooth and delicate thirds of both right and left hands with clear melody lines with distinct shifts in colors
3. Practice tips:
* fingering, fingering, fingering
4. Recommended recordings: Pollini, Hiromi Okada

Practice note - Rachmaninoff, Moments Musicaux, op.16, No.2

1. Goal: irrestible sorrow from the bottom of heart
2. Issues to overcome: clear melody line by right hand octaves and incessant and leggiero interweaving passages by both hands with right balance of sound volume
3. Practice tips:
* left hand only practice with flexible thumb
* deep and clear right hand octaves with flexible wrist and natural weighting
4. Recommended recording: Lugansky, Hemlin

Practice note - Chopin, Etude op.10-2

1. Goal: eeriness of supernatural being like a wind blowing
2. Isssues to overcome: utmost smoothness of legatissimo with weak fingers of right hand accentuated by (but with delicacy) of chords marked by both hands perfectly timied
3. Practice tips:
* follow Maestro Cortot's suggestions on sequence to achieve legato with the weak fingers of the right hand
* flesibility of the right thumbs maintained throughout
* weight center of the right hand shifted outward
* steady yet elegant movement of left hand chords
4. Edititions: Cortot's
5. Recommended recordings: Pollini, Yukio Yokoyama, Lugansky, Hiromi Okada, Claire Huangci (YouTube)