Yes I understand and agree that one can not take any part of the V4 mesh and create a redistributable model from it. For example you can not cut off the scalp area and offer that as a skullcap for Hair Room hair.

But consider a morph target. That must start with the original geometry. It is then "injected" into the figure. It enhances the figure, it does not compete with it and again one must own the figure before you can use the morph.

Weight map data is essentially a look up table of vertex indices against the degree by which they are displaced when a joint is rotated. You can never recreate the geometry from them. They are useless without the original figure.