Original sentence: Krebs received excellent training from Bach, though his counterpoint is considered by some to not be as good as Bach's (Bach is usually considered the master of counterpoint), and, overall, his work is considered of good quality, though at the time it was outdated
Edited sentence: Krebs received excellent training from Bach, though his counterpoint is not as good as Bach's (Bach is considered the master of counterpoint), and, overall, his work is considered of good quality, though at the time it was outdated