I find my favorite musicians are ones that use both science and emotion in there playing/compositions. The emotional aspect is what you notice within the 1st listen, but it is the scientifical aspect that keeps it from getting boring and requires additional listening too fully comprehend.
Guitarists that rely on too much of the emotionally aspect; Santana, great tone and he can really make the guitar weep, but can get quite predictable and sappy.
Too technical: Vai, Yngvie, its cool from a technical point, but again can get quite boring fast for the lack of emotion.
You really can't denounce one or the other (emotion/science)for I think you need an equal amount of both to be a good musician/composer/arranger or whatever.