Tension in the arms starts in the hands. And if you’re pressing the club into the ground as you address the ball, the club can’t move. And the arms will get tight. You need to stay in constant motion. Which is what your waggle should produce. A motion you can “react” to the ball. Versus “act.”. And while you’re staying in motion, the club should “hover” above the ground.
Check out a video about “Hovering”!