Regulating the Tempo
If a fine musical feeling, or sensitiveness, must control the execution of the phrases, the regulation of the tempo demands a kind of musical ability no less exacting. Although in most cases the tempo of a given composition is now indicated by means of the metronomic markings, the judgment of the player must also be brought frequently into requisition. He cannot follow the tempo marks blindly, although it is usually unsafe for him to stray very far from these all-important musical sign-posts. The metronome itself must not be used "with closed eyes," as we should say it in Russia. The player must use discretion. I do not approve of continual practice with the metronome. The metronome is designed to set the time, and if not abused is a very faithful servant. However, it should only be used for this purpose. The most mechanical playing imaginable can proceed from those who make themselves slaves to this little musical clock, which was never intended to stand like a ruler over every minute of the student's practice time.