That's what it's all about. My own personal rule is, "If I can't sing it, I shouldn't try to play it until I can." When something is heard before it hits the hands, it tends to come out sounding like music. When it's only heard after it's played on the instrument, it tends to sound like typing to me. Pianists are especially guilty of this, but I see plenty of bassists fall prey to this mode of playing as well, and it's much worse when a bassist does it because it tends to wreak havoc with intonation.