What determines how impact will look?

When in problem-solving mode, I like to think that a logical approach is to look at the origin, and work outwards using levels of causation. As golf instructors, we problem-solve every time we give a lesson.

I like to consider ball flight as the origin of a golf shot's problem solving. Well, the only things that "cause" a particular golf shot (excluding post-impact factors such as wind, elevation, etc. and factors individual to the tools used such as clubhead and/or ball design) are the things that make up the ball flight model; D-Plane alignments (3D Face Angle and 3D Club Path), Impact location (where, on the face, the golf club hit the ball), and small considerations for Face rotation through the impact interval (this one's theoretical minutia; interesting, but not worth considering). In other words, the only thing that the golf ball cares about is what the club did to it at impact.

So, the next step outwards in this causation chain (in my opinion), is: what causes the club to move the way it does (and thus deliver it into impact in a particular fashion)? I'd recommend reading up on Dr. Steven Nesbit's work around the golf swing. Most of his stuff is available free of charge at the Journal of Sports Science & Medicine site (www.jssm.org). His work deals with the forces and torques that must be present in a golf swing in order to make the club work the way it does. In other words, the only thing that the golf club cares about is what forces and torques were applied to it in order to make it move in the manner it did.

I'd break it down into the: 1) type of force/torque, 2) the timing of the force/torque, 3) the direction of the force/torque, and 4) the magnitude of the force/torque.

In trying to explain these forces and torques that a golfer can apply to the club, I like to say that anything you can do to a golf club can be described as either: pulling, pushing, or twisting. The pulling force refers to moving the grip of the club in the direction that the grip's butt is pointed. The pushing torque would generally refer to the "releasing" of the club head in relation to the grip (think: the grip stays in the same spot, but the clubhead is orbiting around it). The twisting torque would refer to a screwdriver-like motion with the hands/forearms, causing the club head's sweetspot to rotate around the club shaft's longitudinal axis. I feel that anything one can do to a golf club can be described by combining these actions.

Here's my thesis:
Swing positions only matter to serve the application of these torques and forces, but are not important outside of that. In other words, a golfer's swing positions would be at least 3rd in the "chain of causation" of a golf shot, after their impact alignments and force/torque profiles.

In trying to attempt to "improve" a student's swing, I feel that being overly concerned with positions can be dangerous, in the event that you remove the ability to apply the torques and forces in an optimal manner. In other words, a teacher may be able to have a student achieve a "better" position at the top, for example, but the only way it will actually help the student is if they are able to translate that position into a different pattern of more optimal forces/torques.

Here's one benefit to this approach - some golfers may be able to relate more easily, since these forces/torques are "feels" anyways, not positions that they cannot see with any repeatable accuracy.

Now, this approach may not change much of what some teachers say/do to their students, but it may help in the diagnostic process.

Just my opinion...

References:
Dr. Steven Nesbit
Brian Manzella (PGA) www.brianmanzella.com
Michael Jacobs (PGA) www.xgolfschool.com