OK, YouGov, your self-imposed purdah period is at an end. NOW will you answer some simple questions about your methodology and lack of transparency?

You might remember that Laurence Janta-Lipinski's excuse last night for refusing to answer any questions about YouGov's bizarre methodology or their lack of transparency was that an upcoming wonder-blog on the subject had not yet been published on the company's website. It was never actually explained why publication of the blog was such an essential precondition for answering extremely basic questions, but luckily that's now an academic point, because the blog has appeared - and it's written by Peter Kellner himself. So now that it is at last unambiguously permissible under the Janta-Lipinski Doctrine to ask questions (admittedly only "reasonable" questions, whatever that means), I've left the following comment under Kellner's article -

I was told last night by your colleague that once this blog appeared (but NOT before!) any "reasonable" questions asked about YouGov methodology would finally be answered in full. Could you therefore please answer the following -

1) Why are you so obsessively secretive about the voting intention breakdown of the two SNP groups you use for weighting? Why do those numbers never appear in the datasets?

2) If there is logic in separating out Labour-to-SNP switchers from 2011, why not also separate out Lib Dem-to-SNP switchers and Lib Dem-to-Lab switchers, both of whom are very large groups? Surely any reasonable person must conclude that the only reason for the inconsistency in your approach is that you're working backwards to produce the headline numbers that "feel right" to you - and that is hardly something you are capable of being objective about, given that you absurdly declared as long ago as 2011 that it was literally impossible for Yes to win this referendum.

3) There was a YouGov referendum poll last year that asked for people's country of birth, which showed a huge disparity between your sample and the 2011 census figures - you had far too many English-born people and too few Scottish-born people. Given that it's been well-established that being born in England is a strong predictor of a No vote, that by definition means that your headline results would have been artificially skewed towards No. What steps have you taken to correct for that bias in subsequent polls? If you have not taken any such steps at all, why not?

No response so far, but admittedly it's very late at night. We should be able to look forward to a very detailed reply, because these were the undertakings that Mr Janta-Lipinski gave last night -

"we'll have blog up later in the week, happy to answer any and all Qs after u've read it, assuming they're reasonable"

"we are publishing a blog, i will answer all Qs after, on here, email, phone, hell, even face to face"

So it'll be interesting to see if the man is true to his word. Frankly, I'm not holding my breath.

I'll be writing a detailed commentary on Kellner's piece and his (let's call a spade a spade) astoundingly arrogant conclusions when I'm feeling less tired - I'm just back from spending the day in Arran. For now I'll just note what amused me the most about it - Kellner specifically cites the eccentric practice of splitting SNP voters into two distinct groups as a reason for thinking YouGov are right and others are wrong. I'm not quite sure where that leaves Mr Janta-Lipinski's claim that it's OK to be ultra-secretive about that part of the methodology because it's just one trivial detail out of "thousands"!