You can change the shape of your motion path by dragging keyframes in the Value Graph (VG), this is something you couldn’t do in earlier versions. You can OPTION/ALT drag on keyframes in the Value Graph but that changes the interpolation of the Speed Graph. When I first used the Graph Editor I kept trying to option drag out handles on the value graph. I’m really not sure why Adobe choose this behaviour, it makes the Value Graph for Position a bit of a lame duck.
JD
John Dickinson
Motionworks
http://www.motionworks.com.au