Swing guaranteed flexibility, dynamic and rhythmic richness in jazz. It introduced subjectivity and emotion to an art based on regularity. It was the key to freedom with which jazz players placed each one of their notes. Up to that point swing had been related to the asymmetry of ternary phrasing, a term referring to a three-part division not only of the measure but of time in general. Where the classical musician played two equal notes, the jazz player would stretch the first and rush the second, thus creating an impression of elasticity, of rebound. Binary phrasing made a timid entrance into Gillespie's jazz, with the symmetric drumming on the skins of Afro-Cuban drums. But, after concluding that 'it swing' as much in two as much in three, jazz musicians assimilated more and more new rhythmic habits. Starting at the end of the fifties, Latin rhythms (Jamaican calypso, Afro-Cuban mambo, Brazilian bossa nova) were no longer just exotic borrowings but a real part of the everyday vocabulary of jazz musicians; they were a major contribution to the success of hard bop.
The succinct are arrangement for several voices magnified the efficiency of the themes even more. These themes were often inspired by blues or gospel, whose typical formulas they emphasized. Instead of taking the standards from musical comedy and disguising them, as the bop players had done until then, hard bop players avoided them and often favored instead their own compositions - sparser and characterized by a certain brutality, both harmonic and rhythmic.
The rapid chord changes a bebop imposed constant melodic leaps upon the soloist. With time, they learned to find a way of handling these changes while preserving the continuity of their phrases. Hard bop still linked chords without any apparent relationship but no longer weighed itself down with complex developments used to justify these inconsistencies. The same chord could last for several measures, during which the soloist would have all the time needed to structure a melodic improvisation, invent unprecedented rhythmic formulas, prepare the arrival of the next chord, and conceive of an atmosphere that would preside over the dramatic profile of the entire solo.