Query: What type of Chopin's music had the most disregard for strict timing according to Charles Rosen?
Context: There are differing opinions as to how much, and what type, of rubato is appropriate for his works. Charles Rosen comments that "most of the written-out indications of rubato in Chopin are to be found in his mazurkas ... It is probable that Chopin used the older form of rubato so important to Mozart ...