You're welcome Steve :).
I prefer to use the words "constructing" and "building", like if you where working in a 3D program. After all, the figure is a 3D object.
This indeed needs to be considered when drawing the gesture. Even though the focus at this stage is not on forms, the gesture is being performed by the 3D forms of the body so you need to consider how and where the parts attach so your figure doesn't fall apart.
As for modeling, it can based on both an intuitive understanding of form and on the actual lighting. Personally I like to save lighting for later stages of the drawing process. At the gesture stage I focus on analyzing and understanding how the body stays balanced relative to gravity through rhythm. This is what's happening in reality. If you look at the examples in my thread I think it will be clearer.
I hope this helps.If you have further questions feel free to ask.