I will post the videos I make as I teach myself how to use MMD as I go along.
this video demonstrates the results of adding customs bones, weight painting them, adding physics weights and collisions, and joints.
the jiggle comes into play when you add spring and rotational values to all this.
Took one afternoon to learn to figure out. since I haven’t seen no tutorials on this. I will probably make one eventually before I forget any of this.