Many-worlds is contended only conceptually correct, in the same way classical illusions of our billiard ball world are conceptually correct.

Upon reading Collapse Postulates, or If Many-Worlds Had Come First, I would say that Eliezer_Yudkowsky is not merely arguing this correct a la "billiard ball world". Quote from the latter article:

Imagine an alternate Earth, where the very first physicist to discover entanglement and superposition, said, "Holy flaming monkeys, there's a zillion other Earths out there!"

Also, we hang on to the billiard ball view only where we know it conincides with the QM view, as we know that "billiard balls", as a theory, is false. Thus, any predictions derived from it would be suspect unless also derived from QM. None of this seems to me to concide with Elizer_Yudkowsky's view on Many-Worlds.

Summary: I disagree that Mitchell_Porter is arguing a strawman. Also, I have a question: What value do you see in Many-Worlds merely as a concept?