Let us compare the two videos of 9’’ each from Random interesting links and from kPower LLC filing :
The first video shows how the pull of the kite moves the cart in its direction (as for the yoyo mode, the reeling replacing the move of the cart), while the second video (figure 5) shows how the pull of the kites remains mainly in the tether. As a result the power is better applied on the device represented in the first video, and this is very visible in spite of no use of crosswind power.