It's not a problem, you used a smiley face =).

This is directly related to the GreedySolver, which can be preconditioned with a market ordering, as we've discussed in group meetings in the past. This functionality will be useful for any simulation that has 
  a) any facility that competes for a commodity with another (e.g., a reprocessing facility and repository for used fuel) and
  b) uses the greedy solver

It's in the context because this ordering is a simulation constant which is read it via input. It's my understanding that the context is where we put such things so the rest of the simulation (solvers, etc.), can access them...

A more sophisticated solver may or may not use this ordering; the LP solver, for instance, will only use preferences in my current proposal.