With the single consistent theme of the week having been Opposition Leader Tony Abbott's paid parental leave scheme, its cost and, to a lesser extent, that no one other than Abbott on his side of politics thinks it's good policy, the puzzling thing is why the scheme hasn't been nailed down to the last dollar. It's now well over three years old, yet Abbott and shadow treasurer Joe Hockey appear to still not have a clue about how it will be funded beyond the corporate levy, which would get them about halfway, offsets from Labor's scheme, which would get them a little further, and maybe the states chucking in some loose change -- an option rather quickly kyboshed by the senior conservative Premier, Colin Barnett, early in the week.

In Hockey's case, it looked less like he didn't know than that he just couldn't be arsed when he told 3AW's Neil Mitchell that he couldn't recall the funding details offhand because he was in a car.

This is, remember, a "signature policy", and yet despite having -- we're told -- been examined by the Parliamentary Budget Office, it still hangs together with all the confidence of a detergent bubble. It's one thing that the Coalition's Direct Action policy doesn't add up and can't logically work. That's merely a figleaf for Abbott's climate denialism (or, to be pedantic, his belief that the planet is cooling), and to the extent that the policy even survives the transition to government, it will be shredded in the search for budget savings. But the PPL scheme is Abbott's own, his commitment to the women of Australia that he has matured and changed on issues affecting them. Yet, like Direct Action, it seems to have been scrawled on an envelope back in 2010 and left more or less as-is since then, even with the PBO available.