'Touch' in piano playing

I've been thinking recently about the phenomenon of 'touch' in piano playing, in particular when noticing that different pianists have a 'touch' as distinctive as the voices of different singers, and as personal. My feeling is that touch is a kind of 'instinct' that interposes itself on a micro level in the last instant of contact with the keys. It needs plenty of practise and the development of a considerable technique to completely free this instinct and allow it to operate in an unfettered way, but the instinct itself is the one thing in piano playing that is, I think, genuinely unteachable. And it's this that means that pianists who may have been trained in exactly the same 'school' of technique can sound so utterly different from one another (a similar kind of instinct also governs timing at a micro level, pedalling and other aspects of playing). This aspect of 'touch' is intimately linked to a pianist's identity, to who they are and to the unique thing they have to say about different pieces of music that no other pianist can say: Sviatoslav Richter's very Russian but also very individual combination of heavy, melancholic poeticism and eruptions of volcanic fury, or Pollini's brilliant fire and ice. To me it's this unique and particular dimension a musician can bring to the music that is the only really interesting thing in pianism, in singing or in any musicianship. And ultimately teaching is about liberating this instinct!