According to Better Together's own logic, the No lead has slumped by 3% in tonight's YouGov poll

The results of tonight's YouGov referendum poll have just been released, and they show the firm consolidating its status as one of this campaign's extreme No-friendly outliers -

Should Scotland be an independent country?

Yes 36% (-1)
No 53% (+2)

Now, the percentage changes I've listed above are accurate, and are from the most recent YouGov poll in April.  It's worth making the point, though, that the No campaign have for several weeks been insisting that there was a more recent YouGov poll than that - the one conducted by Progressive Partnership.  That's a load of garbage (Progressive are an entirely different pollster with their own weighting procedures), but they've been doing it so they could claim that YouGov were showing a six-point increase in the No lead (in fact both YouGov and Progressive had shown a decrease in the No lead).  So according to the No campaign's own logic, the changes in tonight's poll must actually be reported as follows -

Yes 36% (+4)
No 53% (+1)

In the interests of consistency, we can doubtless look forward to a "Momentum for Yes" graphic appearing on Blair McDougall's Twitter feed any second now.  What's that?  Don't be cynical - of course they're not going to do another "Oceania has always been at war with Eastasia" pivot, and suddenly decide that the Progressive poll was not a YouGov poll after all.  These guys have integrity.

This is also an appropriate moment to repost an observation I made about Kevin Schofield of the Sun (who commissioned the poll) before the results were published -

I was also amused to spot Kevin Schofield almost biting someone's head off for accurately pointing out that the last YouGov poll for the Sun showed a 60-40 lead for No. It's actually normal practice for a newspaper to make the comparison with the previous poll commissioned by themselves, even if the same polling company has conducted a poll for another client more recently.  So clearly Schofield is determined to make the comparison with the poll that gives the highest baseline figure for Yes, in order to push the "momentum for No" spin. He's nothing if not transparent.

So how does tonight's result rank for Yes when compared to previous polls from this most No-friendly of firms?  Pretty well, actually - it's the third lowest No lead reported by YouGov during the campaign so far, only being beaten by the previous two polls which showed leads of 15 and 14 points respectively.  Those numbers are well within the standard margin of error when compared to tonight's poll, so it's perfectly conceivable that nothing has changed, or even that Yes has made further progress.  In normal circumstances you'd say the latter possibility is far less likely, but the situation is considerably less clear-cut when you've just had record-breaking highs for Yes reported by both Panelbase and Survation.  As recently as the 1st of March, a YouGov poll was published showing a No lead of 18 points - 1 point higher than tonight, and yet at the time that was as good as it had ever been for Yes.  It must also never be forgotten that YouGov were showing a No lead of 30 points as recently as last August, meaning that it's still true to say that the gap has essentially halved since then.  So we have a pattern that is at least consistent with the possibility of Yes being at an all-time high across all the pollsters (with the trend being masked in this particular YouGov poll by random sampling variation), but obviously we'll have to wait for further evidence to see if that is actually the case.

We've now had four polls from different firms over recent days (I'm excluding TNS-BMRB because the fieldwork for that was much, much earlier), and three of them have shown decreases in the No lead, with only one showing an increase.  And it's not only the case that YouGov are contradicting a general trend - the extent of the increase they're suggesting in the No lead is less than the decreases reported by ICM, Panelbase and Survation.  The chances that there have been any real world gains for No of late therefore seem vanishingly small - unless of course they happened only over the last few days as a direct result of the absurd reporting of the Lally/Rowling non-stories.  I think that's unlikely, but even if it is the case my guess is that it will prove to be a pyrrhic victory for the Abominable No-Men.  Our lazy journalists may have fallen hook, line and sinker for the 'Cybernat' nonsense, but they'll get bored with it quickly enough, and any temporary benefit the No camp have cynically squeezed out of the whole thing will melt away.

In another sense, You Gov isn't the outright odd-one-out of the four recent polls.  YouGov and ICM may be contradicting each other by showing very different directions of travel, but the common factor with both polls is that they can be seen as reversions to the mean after an unusual finding in the previous poll.  By contrast Panelbase and Survation are both showing tiny No leads that are well below those firm's normal ranges.  So if we set aside the possibility of a very recent swing to No caused by the Rowling/Lally garbage, that essentially leaves us with two roughly equal possibilities - a) the position has been relatively steady recently, or b) Yes have surged to their highest ever level of support.  At least one or two more polls will be required to resolve the uncertainty.

We heard a couple of days ago from someone who took part in the YouGov poll (or at least I assume it was this poll).  He mentioned that he was asked for his country of birth.  I'll be watching like a hawk to see if those figures are published, because on the one previous occasion that YouGov released that sort of data, it turned out they had far too many English-born people in their sample, and far too few Scottish-born people.  If that's a consistent problem for the firm, it could cast doubt on the size of the No leads that they typically report.  We saw with the weekend's ICM poll that reweighting to the correct country of birth target figures from the census was sufficient to reduce the No lead by 2.4%.

As soon as I saw Kevin Schofield mention that a YouGov poll was on its way, I had an inkling that it wasn't going to show further movement towards Yes, because I had only just read an astonishingly conceited article on the YouGov website that effectively said : "We're completely ignoring the fact that other major pollsters are showing a virtually tied race. Only our own polls matter, and because we're showing a wider gap, Alex Salmond will be desperate for a game-changer."  Back in the real world, there is far more than just one possible scenario for a Yes victory.  The first scenario is that Panelbase are the most accurate firm, in which case it doesn't matter if every other pollster continues to show a No lead between now and polling day, and it doesn't matter if the Yes vote in the Poll of Polls never gets any higher than 45% or 46% - all we need is a tiny further swing, and we'll be there.  In some ways that would be the most satisfying way of all to win, because it would absolutely stun the London establishment - but they'd have no-one else but themselves to blame for failing to take the Panelbase results seriously enough.  A second scenario is that ICM and Survation are closest to the truth, in which case a more middling swing is required - although even then it's still possible that Yes could win after never quite taking the lead in the Poll of Polls.  And the third scenario is that the No-friendly pollsters are right, in which case Yes will need a heftier swing and an outright lead in the Poll of Polls - but that won't necessarily require a "game-changer".  The SNP pulled off exactly that kind of swing over a short period of time in 2011 without any specific game-changing moment (unless you count Iain Gray taking cover in a sandwich shop).

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I've been having a look at the datasets from the ComRes regional poll for the Borders and Dumfries & Galloway.  The exact swing to Yes since the previous poll in January is 1.2% (although over on Planet McDougall that somehow constitutes "momentum for No").

English-born respondents make up a whopping 24% of the ComRes sample - I've no idea if that means they've been over-represented, but it certainly goes a long way towards explaining the size of the No lead in the poll.   (For comparison, the 2011 census showed that just 9.6% of the Scottish population are English-born.)  Among Scottish-born respondents in the Borders and D&G, the Yes vote is a full five points higher than among the full sample.

I must say that I think ITV Border are being a bit thick in the way they're approaching these polls.  If they can afford telephone polls of 1000 people in the Borders and D&G, then by definition they can afford Scotland-wide telephone polls of 1000 people.  That would tell us far more, and it would also attract much more interest in ITV Border programmes that release details of the polls (ie. Lookaround and Representing Border).  But as things stand, it's only STV that are bothering to commission national telephone polls - or at least ones that are intended for public consumption.

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SCOT GOES POP POLL OF POLLS

The mild disappointment of the YouGov poll hasn't had a huge impact on the trend shown by the Poll of Polls - the last update showed the lowest No lead ever, while tonight's update merely shows the second-lowest No lead ever.

MEAN AVERAGE (excluding Don't Knows) :

Yes 43.8% (-0.3)
No 56.2% (+0.3)

MEAN AVERAGE (not excluding Don't Knows) :

Yes 36.7% (-0.1)
No 47.0% (+0.3)

MEDIAN AVERAGE (excluding Don't Knows) :

Yes 43.6% (-0.2)
No 56.4% (+0.2)

(The Poll of Polls is based on a rolling average of the most recent poll from each of the pollsters that have been active in the referendum campaign since September 2013, and that adhere to British Polling Council rules. At present, there are six - YouGov, TNS-BMRB, Survation, Panelbase, Ipsos-Mori and ICM. Whenever a new poll is published, it replaces the last poll from the same company in the sample. Changes in the Poll of Polls are generally glacial in nature due to the fact that only a small portion of the sample is updated each time.)

The median is now being calculated as the mid-point between ICM and TNS-BMRB.  Having moved into a more middling ranking with their last couple of polls, YouGov have now reverted to their customary place at the extreme No-friendly end of the spectrum.

The No campaign's lead in the Poll of Polls mean average (not excluding Don't Knows) :

Sep 2013 - 21.6%
Sep 2013 - 21.4%
Sep 2013 - 19.4%
Oct 2013 - 18.8%
Oct 2013 - 18.4%
Oct 2013 - 18.2%
Nov 2013 - 18.4%
Nov 2013 - 18.0%
Dec 2013 - 17.0%
Dec 2013 - 16.8%
Dec 2013 - 16.4%
Jan 2014 - 14.4%
Jan 2014 - 14.2%
Jan 2014 - 14.2%
Jan 2014 - 15.2%
Feb 2014 - 15.0%
Feb 2014 - 15.5%
Feb 2014 - 15.5%
Feb 2014 - 13.7%
Feb 2014 - 13.3%
Feb 2014 - 14.2%
Mar 2014 - 14.2%
Mar 2014 - 14.5%
Mar 2014 - 14.5%
Mar 2014 - 14.7%
Mar 2014 - 13.8%
Mar 2014 - 13.0%
Mar 2014 - 12.5%
Apr 2014 - 12.5%
Apr 2014 - 12.7%
Apr 2014 - 12.7%
Apr 2014 - 12.3%
Apr 2014 - 11.4%
May 2014 - 11.2%
May 2014 - 11.2%
May 2014 - 11.5%
May 2014 - 13.3%
Jun 2014 - 12.1%
Jun 2014 - 12.1%
Jun 2014 - 11.3%
Jun 2014 - 9.9%
Jun 2014 - 10.3%

Last but not least, many thanks to Philip Jack for giving me to permission to use the graph below, which illustrates the Poll of Polls trend in visual form.  It doesn't include the last couple of updates, but it'll give you the general idea!

(Click to enlarge.)