Attached Link: David WM Download

The more elaborate the mesh design and the more elaborate the default shape, the more you need JCMs.

A very smooth basic shape with a very low res simple "fishnet" type of topolgy that just circumscribes the default shape will indeed need very few (if any) JCMs.

A highly sculpted figure with an elaborate edgelooped high res mesh (That means areas of varying density across the mesh) will need JCMs both to smooth the mesh as well as to force it into the desired shape. Weight- and Bulgemaps can only move a vertice in-or out. A JCM can move a vertice in any direction so you're even able to create undercuts.

There is also a huge difference whether you want a Poser figure to be just a stylized representation of a human being, or whether it needs to be a perfectly realistic model of a particular human.

Anyway, apart from the DAZ default JCMs (Ellbows, kneecaps), the only JCM I made for David-WM was to smooth the buttock/crotch bend.

I said I won't mind if anyone wants to improve and then re-destribute him, so if anybody feels adventurous, try to make him bend just as well (or better) without any JCMs. (The poses shown here are supplied in the download)