The mention of Memphis and FedEx makes me think of a problem set I did in college, I think for an AI class.

It involved calculating different types of distance, such as Euclidean distance, Manhattan distance, and Memphis distance, where the Memphis distance was calculated by routing everything traveling through a single hub. We were told that it was called this because it used to be that all FedEx packages, no matter where they were going, were sent through Memphis. Googling for "Memphis distance" didn't seem to turn up anyone else using the term the same way though, so I'm beginning to wonder if I imagined it... I don't suppose anyone else has ever heard of it?