Pianist Stephen Hough discusses the practice of practising:
My teacher, Gordon Green, used to say, “in practise a perfectionist, in performance a realist”. In other words, prepare assiduously, tirelessly at home, but when onstage accept the situation at hand without wishing the piano were more in tune, the audience were more appreciative (or larger), you hadn’t made a mess of that octave passage and so on.
But being a “realist” sounds rather prosaic when faced with bringing to poetic, passionate life the masterworks of master composers. I might put it differently from Gordon: in practice an engineer, in performance a pilot. Nuts and bolts in a plane are incomparably important, but when you sit at the cockpit of a Steinway concert grand your eyes need to look ahead not underneath.
The purpose of practising is so that we (offstage as engineers) make sure that we (onstage as pilots) are completely free to fly to the destination of our choice. That destination is one involving imagination and creativity and spirituality and danger and ecstasy of course, not merely the A to B of playing the notes, but without the nuts and bolts in place we will never be airborne. The greatest interpretative vision of the final pages of the final sonata of Beethoven will nosedive to oblivion if we can’t play an even trill.
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Slow practice can be a complete waste of time if the mind is not working quickly. Simply to trawl through passages like a contented tortoise is a waste of the felt on your piano’s hammers. Good slow practice is more like a hare pausing to survey the scene — sharp in analysis, watching through the blades of grass, calculating the next sprint.
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There are two dangers to avoid in practising, firstly not to play as if you’re onstage, filling the hours crashing through pieces without improvement. This is a common occurrence in conservatories — Rachmaninov concertos pounded with adolescent passion and coarse, crude effects. But the second, more subtle danger is not to get stuck in a practising mode. This is related to mindless slow practice. All the focus when in the practice studio should be how we will play when in the concert hall. If something comes apart, don’t stop immediately. Guide the skidding wheels around the crashing corner for another meter or two, despite the sparks and screeches. A common student scenario: music flying along; train wreck; a second of silence; start at point of accident; continue. The point where things broke down is the fragile spot, the dodgy seam. It needs sufficient overlap of material to be strong. Go back before the mistake and practise beyond the mistake — then the mistake itself will be more safely repaired. Otherwise the very stopping and starting becomes a reflex — an ingrained repetition of breakdown.
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There is a well-worn saying: practice makes perfect. I don’t believe this, at least in reference to playing the piano: abstract “perfection” is rarely what we seek; but good practising makes it more likely that we will give a good performance. Its attention, its concentration, its tightening of the screws enable the concert experience to take wing in freedom.