[mb6606]

Vertical and horizontal hinge both have very good ball compression characteristics.

Keeping the loft of the club out of the equation, the vertical hinge action itself will impose back spin while a horizontal hinge action will impose side spin. We're talking as perfec as it gets here, and then a horizontal hinge will produce a draw. This is layback without closing vs closing without layback.

If we're talking about a human golfer it is very difficult to anticipate that all other alingments can be the same. Dual Horizontal hinge has the largest clubhead to hands speed ratio, while vertical hinge has the smallest. So if the clubhead speed is the same, the vertical hinge will have greater hands speed, and thus a greater effective swing arch and more effective mass-velocity to back up the collision with the ball.

As long as the vertical hinge can keep up with the horizontal - which isn't very long - I guess you will get more ball compression due to the faster hands.

The question was based on all things being equal. The ball is on the clubface for 1/2 a millisecond. Therefore compression has to be equal. VH allows one to add loft versus HH. So for less compression the face would have to be layed back more at impact (therefore it is no longer equal).