But in an interview I heard a professional performer answer: "I don't mind to play every night the same repertoire, because that's not the point. The essence is to enter into the play. That can be done every night again with the same numbers".
A commitment for 'something new' as well as a need for 'exercise' doesn't fit into the playful world of enjoying music. They come from the world of 'survive' where you have to do your duty and things you don't like in order to earn your money.
Expending 90% of your playing time doing exercises not only is unpleasant, but you also have the risk to have a wrong radiation during a possible performance.
An important criterion for the quality of art is the entering into. This will be done poorly if you have to do your best too much to meet the demands of the art. Every piece of art has them. E.g. a composer may get an order to make a requiem of a certain length and orchestra.
The question is, do those two aspects agree with each other: spontaneously acting according to the entering into your play and still rationally keeping control over your feelings in order to meet the demands?
For a master like Bach: yes. His mind was so playful he sometimes even put symbolism in his works. Great composers always have kept to the rules of a certain form, e.g. those of a sonata.
Is it possible for us, amateurs, to meet demands besides entering into a song? Perhaps not, but we may approach it like a challenge to take the professional masters as an example.
In the previous lesson the demand was to stick to the chord scheme of a given song during our improvisation. In general the song form (A B A) is suitable to give structure to an improvisation.
Demands improve the quality of an improvisation. If you don't stick to
the chord scheme of a song like 'It's a long way to Tipperary' it will
Hear the song with the correct scheme and then wrong, as the modulations are neglected.
It is only possible to meet the demands if we know the song well. Consequently we will have to play it often. So we will have to play a song over and over again, but not in an atmosphere of exercise but playfully and full of creativity.
Creation is only possible in a relaxed atmosphere. We must try to achieve we like our own play even if we always improvise on the same songs. It are the variations that count. The real art is in the details: the touch of a tone, the little taking back of the tempo and for improvisation of course the melodic variations and findings which amuse the listener.
We are our own most important audience. Nobody listens more intensely to our play than we self do. And if we play in this listening way, also others will like us best.