I think something being "Melodic",or notes that resonate together naturally and then "Congruent" or agreeable, would explain a lot of Rock, blues, country and Pop music we listen to. Jazz on the other hand, and other types of hypnotic musical patterns Can possibly not be congruent with a base melody or base chordal structure. So it can be both depending on the Genre you speak of. I think Jazz is not always like this, but it can be due to its loose structure. You could argue that diminished scales and chords are not quite congruent, but then again they are since they are explained to be grouped as such.
It can be vise/versa, but for the most part congruently attaching notes to perform a melody is common for our ears and minds to enjoy the layering sounds, even stimulate emotion. Non congruent musical patterns and notes can sound confusing and fragmented, maybe even painful. Almost like a 3 year old playing a guitar or piano.
Then there is the power of being a known master of music and playing fragmented with this aura of stage authority. That "perception" of the guy meant to play it that way may can actually make it legitimate music. So Perception is actually tied up in all this, IMO. I guess someone waked and baked today....
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