[mr_luc]

Well, I haven't solved that part!

Nor do I think the permanence-of-marriage problem is any more or less solvable than the disadvantaged-single-parent-children problem.

But the permanence-of-marriage problem interests me, at least in my case.

And it seems like a problem that can be addressed in ways that improve outcomes, even granting that it has random/unknowable components.