This is where your image can be radically altered. We've warped the image, the pins still move independently but click the 'main' vertical plane with shift held down and your grid-line will turn yellow. Now your vertical plane (and the two pins at either end) act in harmony (although the other four can be used for final adjustments).
In this way, both the perspective and elevation of your image can be adjusted.
It does get easier! Keep referring back to the video.