In his Memoirs Berlioz recounts an exchange with Mendelssohn that took place in Rome in 1831. ‘What on earth is the point of a metronome?’ Mendelssohn had asked; ‘Any musician who cannot guess the tempo of a piece just by looking at it is a duffer.’ Berlioz said nothing, but later enjoyed Mendelssohn's annoyance when, looking at the newly completed manuscript of the Roi Lear Overture, Mendelssohn turned to Berlioz and said ‘Give me the right tempo’. ‘What on earth for?’ replied Berlioz, ‘I thought you said that any musician who couldn't guess the tempo was a duffer?’

Unlike Mendelssohn and Brahms, who also scorned the metronome, Berlioz approved of it and used it all his life. A passage in Le Chef d'orchestre confirms his faith and offers a judicious note of caution:

I do not mean to imply that he must copy the metronome's mathematical regularity; any music done that way would be stiff and cold, and I doubt that one could maintain such level uniformity for many bars. But the metronome is, all the same, excellent to consult to establish the opening tempo and its main changes.