By Paul Goodman
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Imagine for a moment that you are a male backbench Conservative MP – perhaps a member of the new intake, or one first elected in 2005, or one of the over 25-strong group of former Shadow Ministers during the last Parliament who didn't become a real Minister after the election.
Now presume that you want to become such a Minister (no great surprise there: most MPs do). How would you assess your chances of promotion when the Prime Minister carries out a big reshuffle, probably next May in the wake of the annual cycle of local elections?
You would probably begin by counting the number of Government Ministers – including Whips. I make it a total of 90 Commons Ministers – not including Parliamentary Private Secretaries, who vote with the payroll.
You would then try to guess how many present members of the front bench David Cameron will dismiss. He is known to believe his team is doing a good job. My imaginary MP might calculate that at the most the Prime Minister will dismiss a fifth of Ministers. I think that such an estimate is rather on the high side, but I can see why backbench MPs might make their hope the father of the thought. (Politics can be a selfish business.)
That leaves 18 vacancies. Not many spare places, you may think, for 231 Tory non-Ministers to fill.
But this vacancies figure is deceptive.
This is because although there are 90 Ministers, 15 of them are Liberal Democrats. It must be assumed that this number (or at least this proportion of the whole) isn't going to change. So the correct figure to subtract a fifth from is 75, not 90.
That leaves only 15 vacancies.
But that figure is deceptive, too.
This is because of the female factor. In Opposition, Cameron promised to aim for a third of Ministers being women in a Conservative Government. The recent reshuffle was consistent, since it saw the promotion of Justine Greening and Chloe Smith (plus that of Claire Perry as Philip Hammond's PPS), with the implementation of that aim as far as the Tory Ministerial posts are concerned.
At present, 9 of the 75 Conservative Ministers are women. Were the Prime Minister, therefore, to ensure both that every single one of the 15 Ministers he dismissed is a man, and that every one of their replacements is a woman, he would still be short of that requisite third (just).
However, he will almost certainly not attempt to hit any target of a third of his Ministers being women all at once, and he also has the Ministerial posts in the Lords available to him if indeed he's trying to achieve it.
So I were I our imaginary male backbench Conservative MP, I would calculate that the Prime Minister will appoint women to roughly half the 15 posts.
That leaves – at best on this calculation – eight vacancies only (with 190 male non-Minister Tory MPs chasing them, while 41 women chase seven places).
But – yes – that figure of eight is deceptive, too.
This is because it is open both to male backbench Conservative MPs and male Conservative PPS's. Some of the new Ministers will be drawn from the ranks of the latter. Were I our imaginary male backbench Conservative MP I would calculate at least three. That leaves a figure of five.
However, yet again, that figure is…but you've guessed it.
This is because some of these five will be appointed to the whips office – two, let us say. So after the smoke has cleared, we are left with…a figure of just three male backbench Conservative MPs who will be appointed as Ministers come the reshuffle.
I'm sorry if I have miscounted any known figure, appreciate that my "guesstimates" are speculative – and acknowledge that the whole exercise is arguably trivial.
However, that is not how your average-to-goodness member of the new intake, or MP first elected in 2005, or MP who is one of the over 25-strong group of former Shadow Ministers during the last Parliament (but who didn't become a real Minister after the election) will see it.
Even they haven't done the numbers, or calculate them differently, they will none the less be thinking about all this. My assessment won't be that different to theirs. It may matter both when this afternoon's vote comes and in the future.