Great video! I tried this method and had some issues but from this video i realized that when i alt click the x and y keyframe i could easily pick whip the x and y coordinates to the position keyframes of my null object without having to write any overcomplicated expressions. So all in all, this helped a lot. Thanks! 

#hangoutsonair

This is literally the most obscure thing I've ever seen. Thank you for this

this was released fyi