[Mathew]

But the crucial point is that at Impact (not Low Point or Separation), the clubface must be open to strike the ball on the inside-aft quadrant. Even if the clubface is very slightly closed at Impact, it won't contact the ball on the inside-aft quadrant.

At Impact the sweetspot should travel through the inside aft quadrant which may or may not be the initial contact point dependant on the clubface orientation.... Quite simple really.....