Looking at the page for Versatile Plastic, I have to concur with barkingdigger that this seems to be telling me things I already know. In fact, I know
more than it's telling me, because I know from experience that the most intuitively compact arrangement might not be the one Shapeways considers to have the least "machine volume."
Specific information that seems to be missing:
How these two are weighted relative to each other, and at least rough guidelines on how "machine volume" works.
What actual difference this makes. (e.g. does a model with two parts cost the same as two separate models?)
Which of these are affected by something the user does. (Obviously the price differences between types of Versatile Plastic fall into this category, but I have no way of knowing if, for instance, larger models cost more to process and/or dye, other than experimentally.)