A question on Parallelism: Page 128 Manhattan SC BOOK, 5th

[AZ679]

Manhattan SC book, page 128, 5th Edition

This sentence appears on page 128:

"Beethoven's music, which broke a number of established rules with its structure and melodic form, is considered more revolutionary than Bach."

On page 129, it is said that:[color=#4000BF] "We could also write that of Bach at the end of the sentence."[/color]

My question: Doesn't the usage of 'that of Bach' violate the parallelism between Beethoven's music and Bach's [ music understood].

Which one is preferred with respect to style?

[RonPurewal]

both are correct.