[no_mind_golfer]

Not sure I follow you but...

Take a dowel rod... that represents the shaft. Take a push-pin or nail and put it in the end. Find a hex nut and tie it on a string then tie the other end to the nail or push pin on the dowel. The nut is the COG of your "club head. Take it out side and swing it every which way...up, down inclined... it doesn't matter. The Nut will never move off the plane of the swing (as defined by the dowel). The nut dutifully follows the shaft (unless/until it "releases" in the plane of the swing not perpendicular to it). There is no physical force/torque which causes the club face to open and close besides that which is supplied by the golfer's hand. Golfing machines use gears to achieve what the golfer's hands do naturally.

http://www.golflabs.com/Images/tse_4.jpg

The club is on a tilted plane, and thus has the 'out' of down, out and forward built into the physics of the machine and the design of the club.

IF

the machine is perfectly on plane - the line of pull.

The design of the club will pull the toe 'out' for proper impact. Try swinging a hockey stick, or any number of aids that exagerate the 'toe' of a club, they force that shaft to turn around the COG - sweetspot.

A perfectly on plane swinger, or machine, doesn't need to cause the out. Realistically, nobody is that perfect, so the release is often 'caused' by the golfer (release swivel).

the design of the club, and the physics of the COG plane, require that the shaft rotate around the sweetspot (per Ted's baseball bat example).