Wout, pull on the end of the pole is vertical, or a tiny bit aft of vertical. Pull on the hound fitting is far more forward than down, thus the net effect is that the spin generates forward "pull". Tell me if I'm wrong, but the lift of a sail flying free is perpendicular to its luff. This image of an 18 skiff, admittedly with an exaggerated pole length and luff angle compared to most cats, shows the general orientation of the kite to be maybe 35 or 40 degrees aft of vertical. This will clearly degrade the amount of forward thrust available to pull the boat through the water. However, the total thrust or pull generated by the kite is unchanged. If the vertical component is greater than the "tripping" component of drag caused by the greater speed, then the kite will without doubt lift the bows.