This is a traveling salesman problem, so it is unlikely that Thomas used an algorithm that guarantees optimality. If I understand your proposed greedy algorithm correctly, the distances at the beginning would be shorter than the distances at the end, which I do not observe in his list. A greedy heuristic that would not produce that effect would be to consider the state to be a bunch of lists and at every step concatenate the two lists whose endpoints are closest. This is a metric TSP, so the Christofides algorithm is no more than 1.5x optimal.
This is a traveling salesman problem, so it is unlikely that Thomas used an algorithm that guarantees optimality. If I understand your proposed greedy algorithm correctly, the distances at the beginning would be shorter than the distances at the end, which I do not observe in his list. A greedy heuristic that would not produce that effect would be to consider the state to be a bunch of lists and at every step concatenate the two lists whose endpoints are closest. This is a metric TSP, so the Christofides algorithm is no more than 1.5x optimal.
You are right. I’ll call this sorting order Levenshtein-TSP ordering.