Hi Michael,
Thanks for the link, it's interesting reading. When it came to applications within ArcGIS I suspected that it wouldn't necessarily be directly implementable.
Yes, I did think that VRP might be the way to do it, I've been experimenting with setting capacities and pick ups as binary constraints for a route between fixed "depots", but have yet to figure out the exact work around. Any advice you have would be greatly received.
The specific application I'm interested is related to the an individual's food environment and the notion of 'trip chaining', so I'm hoping to get a sense of the area of opportunity, or activity, for individuals who might wish to visit a set of particular types of food store (i.e. markets, butchers, grocers, discount retailers etc.) from their home location, or between paired locations like home-school, home-work. I'm exploring the idea that you could derive a measure of opportunity, or efficiency, by looking at the extent to which particular chains deviate from least cost routes, and how this might relate to behaviours.
In this sense we're talking a limited number of types, maybe 3 to 5, but within each type there is the potential for a largish number of facilities (up to 50 for a constrained local area, or particular route) depending on the local density of food stores.