How to Reconcile interfaces on a NetFlow node?

Need a little help understanding how to use the ability to Reconcile the interfaces on a NetFlow source node.

Do you do this from the vantage point of the NTA collector? In other words, do you picture a network diagram from the Orion collector through to each of your flow source nodes and then set the Direction for each interface based on how network traffic actually routes back to the collector?

Any help would be greatly appreciated.