The chorus master believed that reiteration produced confidence. (reiteration: repetition, restatement, reassertion) His singers suspected that unremitting repetition would inhibit anyone's willingness to sing. (unremitting: incessant, relentless, ceaseless; inhibit: restrain, hinder, impede) An hour of reinforcement was laudable; five hours on the same three notes made the youngest singer irritable and the oldest insensible to corrections. (reinforcement: strengthening, support, bolstering; laudable: praiseworthy, commendable, admirable; irritable: short-tempered, touchy, testy; insensible: unaware, unconscious, unperceiving)
A particularly refractory passage began with a leap that scarcely troubled them individually. (refractory: stubborn, recalcitrant, intractable) Together they waited for somebody else to begin. The stage manager thought the difficulty more tractable than it sounded. (tractable: manageable, amenable, compliant) She asked each singer to start as if nobody else were there.
The chord rang cleanly. The master called it luck. She asked him to relent for the evening and test the theory again tomorrow. (relent: soften, yield, give in) The following morning the notes were still there, along with every member of the chorus.