I'm wondering if it's possible to animate a scale of a layer independent of it's mask so that the mask stays locked but the layer moves. Like in Photoshop you can unlink the mask from the layer.
The only way I can see how to do this is to pre-comp the layer, mask the pre-comp, and animate it's stuff in the pre-comp.
Pls let me know if there's a better way to do this!
You can also use Set Matte. There are lots of ways to skin this that cat.