Leaving aside the bad prosody and the minor defects in taste, we have left a work which shows a wealth of invention, melody, and sparkling fancy comparable to Gretry's.
Gretry was no more a great musician than Offenbach, for he also wrote badly.

The essential difference between the two was the care, not only in his prosody but also in his declamation, which Gretry tried to reproduce musically with all possible exactness.

He overshot the mark in this for he did not see that in singing the expression of a note is modified by the harmonic scheme which accompanies it.

It must be recognized, in addition, that many times Gretry was carried away by his melodic inventiveness and forgot his own principles so that he relegated his care for declamation to second place.
What hurt Gretry was his unbounded conceit, with which Offenbach, to his credit, was never afflicted.

As an indication of this, he dared to write in his advice to young musicians: "Those who have genius will make opera-comique like mine; those who have talent will write opera like Gluck's; while those who have neither genius nor talent, will write symphonies like Haydn's." However, he tried to make an opera like Gluck's and in spite of his great efforts and his interesting inventions, he could not equal the work of his formidable rival.
* * * * * Although he was not a great musician, Offenbach had a surprising natural instinct and made here and there curious discoveries in harmony.