What if the OP had used the word "percussive" instead of "percussion?" Why do some players prefer the attack of a pick and others the attack of the fingers? Doesn't that speak to percussiveness as opposed to rhythm? Rhythm is established by the meter and duration of notes; percussiveness is defined by the articulation of your notes. So, some player's styles are more percussive while still being rhythmic (and potentially harmonic and melodic) while other player's styles are more focused on rhythm, harmony and melody only (or some assemblage thereof).
