A major design change in modern clubs is to increase the size of the sweet spot on the club face.

The geometry of your club and club face also are very important.

During impact, the club face deforms slightly, and then rebounds.

"I can't even get the club face on them."

"I guess I hit it in the middle of the club face," he said with a smile.

In the test, an air cannon shoots a golf ball at the club face.

The club face stays open and the ball goes to the right.

It's not a swing you would teach, with a strong grip, closed club face, the head coming up.

In this case, the club face had gone through just that one millimetre too low under the ball.

I hit the ball on the top of the club face, the wind got it, and away she went, into the water.