On Perfect Guitar page insert a new link to the list titled &gt;&gt;&gt;Harmonic nodes and pickup placementHarmonic Nodes are not relevant to pickup placement because they are not in a fixed position.  Nodes shift position according to which note is fretted so there is no persistent relationship between nodes and sonic timbre, and when nodes occur over the pickup pole the effect is negative since relevant harmonics are cancelled.The sound of pickup positions is more a function of the distance from the bridge ..... the greater the distance the less sharp (attack) and less focused the sound becomes.  It's a sliding scale of change.There is no optimum placement for pickups since players have different preferences, and anyway will usually adjust to the sound the instrument is delivering.