The expression is… ‘the dog wags it’s tail’ not… ‘the dog flings it’s tail violently’.  The arms need to work in harmony with the body turn to hit great golf shots…

To hit solid square faced golf shots, we need to recreate the triangle formed by the hands and shoulders that we created at address back at the golf ball.  I have seen far too many swings where the shoulders turn back through the ball far too quickly for the hands and arms to get caught back up in the race back to the ball.  The result is the thin or topped shot as the target shoulder is too high at impact, or the pull/ slice that the ‘open’ shoulders create.  The shoulders pulling the arms back toward the ball needs  to be accompanied by the trail arm ‘pushing’ the hands back in front of the chest towards the  moment of truth.  As the hands arrive back in front of the chest, the forearms naturally square the clubface and we create the extension through the ball that delivers maximum club head speed.  In short, we need to wait for the hands and arms to get back to the ball before the shoulders have gone well past.
An excellent drill to keep the arms and body turn working together is to take ½ to ¾ swings with a PW or 9 iron with head covers or golf gloves tucked under the armpits.  The secret is to not drop them as you swing back and through.  This drill synchronizes the arms and body turn and keeps the arms extended with the hands out in front of the chest.  We need to ‘swing’ the arms, not ‘fling’ them.

See you on the range, Dave