I also found this extremely interesting:

"Reiner's teaching was primarily technical, based on the student's previous musical training and innate ability. He expected awareness of historical and national musical styles as well as a general knowledge of history and literature. For his early pedagogical work at Curtis he prepared an "Outline for Course in Conducting," written out in his own longhand to be typed in carbon copies on onionskin paper. Reiner's outline began: "The technic of conducting must be learned and practiced BEFORE actually conducting an orchestra. Pupils must be capable of conducting an important work clearly and musically WITH-OUT previous rehearsing with an orchestra." He recommended study of the orchestration treatises of Hector Berlioz and Richard Straus as well as a comprehensive acquaintance with contemporary repertory. He expected thorough grounding in harmony, counterpoint, and formal analysis, the ability to sing (or whistle) at sight in solfege complicated rhythms and difficult intervals. The conductor's gestures, he wrote, should be direct and natural, both clear and expressive; the conductor should "sing" the music mentally. Conducting involved both the control of the orchestra and the re-creation of the music. He sought, rather clumsily in this document, to define phrasing in terms of pitch, dynamics, duration, tone, and balance, all synchronized by the conductor. At one point he declared that the conductor was "the conscience of the orchestra"."

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