I'm not exactly sure, but I think the underlying philosophy here is that code is a lot more like math than like music, and you can't copyright math. So to have

I'm not exactly sure, but I think the underlying philosophy here is that code is a lot more like math than like music, and you can't copyright math. So to have any copyright protection at all for code, the Office had to carve a narrow trail where the standard for copying is higher, because there are plenty of circumstances where there is only one right (or most optimal) algorithm, and there's no protection for the algorithm itself.