Most golf instruction at one time or another talks about keeping your head down, or quiet. I agree that the head should stay pretty quiet during your backswing but find that keying on what the head does during the downswing and impact is more important. One of the Cardinal sins in golf is getting your head in front of the ball at impact. There's no way you'll ever square the clubface up and hit the ball straight if your head gets in front of the ball. Tour pro have their head well behind the ball at impact and you should too.
A neat tip or idea is seen in the photo. At impact, if you thought of holding a phone between your left ear and shoulder, much the way you would if you were talking on the phone and picked up a pencil and paper to write something down, it will do a nice job of keeping your head behind the ball through impact. When you head is back your arms and square up the club face and do their job nicely.
