I am new to. So I am honored that I get to participate in your thread! I believe that my long iron success is due to my smooth swing tempo. I like to emulate two golfers that are no longer with us unfortunately. Payne Stewart and Sam Snead have the greatest tempo that you can see on a golfer. Phil Mickelson and Ernie Els may be close, but they dont have an obvious dying momento that finishes on the back swing like Stewart and Snead have.
Watch these swings and notice that thier tempo and release power start about when thier hands are on the side of the body. This gives you the OPENING to make great contact. While most amatuers like myself start the power on the top and come down too fast. This will create a snap hook, top the ball, or slice if im lucky to catch it. And the power is wasted plus the probability of good contact is compromised.
But once you establish and smoothen your tempo, impliment confidence and target commitments instead of mechanics.