[Daryl]

Well thought Daryl. The two frameworks seem somewhat differnt to me, but not mutually exclusive. I think the biggest difference is that TGM is more clear about what happens during the impact interval (hinge action) while Joergensen's D-plane is a more explicit and systematic and perhaps more accurate description of what TGM says about D-plane-ish character of the ball flight.

Not quite sure about this though:



How do you see it loose contact with the impact point? By rolling up the club face?

I have a driver that is cryo treated or something. Very hard surface that I can still use as a mirror after 5+ years of use. It's by far the best driver I've ever used. But I can't use it in rainy weather. If both the ball and the club face isn't dry I get very little back spin, only 50-60% of normal carry and a sometimes a weird ball flight.

This must be due to hydro planing or some other mechanical condition that reduces the friction significantly. I'm thinking the former. But this shouldn't affect the quality of compression as far as I can see. And it doesn't feel like it does so either. I am guessing a glancing impact with good ball compression here. But that's only a guess.

I imagine that Contact is lost because the Clubface moved around the ball. The Ball doesn't slide, the Driver Face Slides.

When the Ball and Clubface are wet, the force of Impact transfers the water from the ball to the face of the driver. The Driver face was almost dry by the time it struck the ball. As impact occurs, water is forced away from the impact point and compresses at the impact perimeter.

As the Driver Face moves through the Ball location it's provided with a steady spray of water (at 100 MPH). This interrupts the flow of water away from the impact point perimeter. Water at the Top of the Impact perimeter will escape upwards because of the Sloped Driver face(but not fast enough). But water at the bottom of the Impact perimeter will also escape upwards, into the Impact point. Keep in mind that you're creating as much compressive force on the water as you are on the ball but water flows easier than a solid. As the ball begins to separate from the clubface, the clubface hold on the ball is at its weakest and the water pressure is at its greatest. It's that moment, I imagine, that the slide occurs. So even though it may feel like a solid shot because you feel the heaviness of Impact, compression was lost when the clubface/ball contact was most vulnerable.

Dry the Ball before placing it on the tee and the bottom of the ball may stay dry enough. Grooves on the Clubface help relieve the water pressure but only to a point, until they're filled.

As the Driver face slides down the ball, farther from ball center, compression is relieved at the initial compression point and the ball will travel less distance. It will also have a higher launch angle. Reduced Backspin will cause the ball to wobble in flight.

One drop of water is more than enough to wet the entire contact surface between the ball and clubface. But to get that driver face to slide, we're talking about a lot of water. At least 5,6,7,8,9 drops.

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The D Plane may be able to add additional material for TGM but not to the science regarding collision. Only what happens afterward.