Postscript on the role of metaphysics
Interesting discussion so far. I wanted to add a few notes to further refine my thoughts about this issue. To begin with, I am leaning toward the conclusion that there is no such thing as metaphysical necessity. That’s in part because one cannot find metaphysical laws, and in part because I doubt there is such a thing as necessity, period. Nothing is physically or logically necessary - only possible or impossible.
True, once we establish certain constraints - for instance the laws of physics in our universe - then certain things necessarily happen. (Indeed, if you are a determinist, everything necessarily happens.) But there doesn’t seem to be a reason to think that the laws of physics themselves are necessary (multiverse and all that), so…
The same goes with logical necessity: once we pick certain axioms or premises, a number of things necessarily follow. But we could have picked different axioms or premises, so that those very same things wouldn’t follow at all.
Where, then, does that leave metaphysics? I still think it has a role to play, in the same sense that philosophy in general has a role to play. I have come to see philosophy as a type of critical inquiry that bridges logic (broadly construed) and science (and other sources of empirical knowledge), in the sense that it applies rigorous reasoning to whatever the issue at hand may be (e.g., ethics) while taking into account empirical input. This is nothing new: it is a restatement of Kan’t compromise between rationalism (the idea that one can derive a priori truths about the world) and empiricism (the idea that all truths derive from sense experience).
Similarly for metaphysics: I see it as a bridge between the Scylla of logic and the Charybdis of physics: the role of metaphysics is to make reasoned sense of what the natural sciences tell us about the world (in this I’m with people like Ladyman and Ross), as well as to elucidate how that knowledge fits with our understanding of abstract objects, such as mathematical and logical relations. But there are no laws of metaphysics, just like there are no laws of philosophy, so this endeavor is one of critically making sense of things, not of discovering or dictating how things are.
At least (again), this is what I think this week...
 Non-locality does not apply to macroscopic objects of the size of a human being, for reasons that not even quantum physicists are particularly sure of.