[nocipher]

It is not the presence of an internal heuristic that makes an algorithm greedy, it is the choosing of locally optimal solutions. For your claim to hold, you would need to demonstrate that people make locally optimal solutions, at least in the context of this problem.

That is most likely a wrong assumption. Greedy algorithms usually do not find globally optimal solutions, yet the people solving these problems are finding -the- solution. That is enough to suggest that the heuristic people are using is much more complex than merely choosing local optimums.