"To influence a clear, singing tone with the left hand, to phrase it
properly with the bow hand, is most important. And it is a matter of
proportion. Good phrasing is spoiled by an ugly tone: a beautiful
singing tone loses meaning if improperly phrased. When the student has
reached a certain point of technical development, technic must be a
secondary--yet not neglected--consideration, and he should devote
himself to the production of a good tone. Many violinists have missed
their career by exaggerated attention to either bow or violin hand. Both
hands must be watched at the same time. And the question of proportion
should always be kept in mind in practicing studies and passages:
pressure of fingers and pressure of bow must be equalized, coordinated.
The teacher can only do a certain amount: the pupil must do the rest.