Manipulating Skinned Cloth Coefficients, how to?

Hi.
I’m trying to set manually the skinned cloth coefficients with values from textures.
Actually I wouldn’t bother if the Skinned Cloth editor worked… Anyway I can’t figure out how are the coefficients correlated with the vertices.

The base Cloth class provides a vertex array and says its length can differ from the corresponding mesh.
Actually the vertices array here results of the same length as that of the mesh, while the coefficients array is smaller.

So how do I get from a coefficient to a mesh UV or vertex?
I understand the verts can get collapesed for skinned mesh, but if I had the correct original position then I could at least search for nearby vertices and their UV’s (I’ll deal with seams somehow).

Thanks.

same question here but with the new u5 cloth system.