This deformation is not done with cageEdit. The last on this picture is a subD last, and it is morphed from one mesh (hidden) to a target mesh. I used the GH plugin fattener by Daniel Piker to achieve this. This has a component to morph a mesh (in this case the control polygon of a subD) from a reference to a target mesh.
After the morphing of the controlpolygon the SubD is regenerated. See
