The pianist inhaled expressively at the first note and did not exhale until the last; the music turned blue and eventually fainted.
You have to play the piano ultimately as if you invented piano playing. And indeed one has to re-invent piano playing for one self. One has to wield ones art like a holy flaming sword.
A sonorous tone, an orchestra at your finger tips, a brilliant balance, singing at the piano ... are all matters of creating a particular sound that you imagine and want to hear, a desired sound.
The end of a piece must be a confirming statement or a tender good-bye, not an rustled apology or a rushed IED.
In every solar system in the galaxy is a range around the sun within which the ideal distance and trajectory for a life sustaining environment is provided. Astronomers and astrobiologists term that range the Habitat- or Life Zone, colloquially the "Goldilocks Zone", the "just right" distance from the sun. Not surprisingly our planet is in the Goldilocks Zone around our star - 2% further out and global glaciation would envelop the planet.
When you warm up before a performance, don't just warm up your fingers: warm up your ears, your musical mind, your artistic soul!
When you rehearse alone before a concert, you can and perhaps should play at a slower tempo, but under no circumstances should you play with diminished dynamics.
“With expression your performance repertoire rehearse you must!”
When we have a melody in octaves, usually we'd lead with the high and sometimes with the lower voice. But try to sing the octave as a compound sound like strings can and do.
Fingerings often subdivide in different places in parallel passages ~ e.g. scales with both hands over 4 octaves, the howling wind over the graves in the last movement of Chopin’s Bb-minor sonata, the playful wind over the steppe in the last movement of Tchaikovsky’s concerto in the same key, and such. It is the performer's right to choose which hand to give leadership to.
If it is challenging to play difficult parallel passages together fast, one should not only lead with the left hand, but group (subdivide) by the left hand. The right choice then is to master and obey the left.