In the immortal words of Peter Snow (possibly modified slightly by Rory Bremner) - "It's just a bit of fun, that's all it is!" I decided to use the seats calculator at the Scotland Votes website to see what the composition of the Scottish Parliament would look like if the 6.9% swing in the Dunfermline by-election was replicated across the country at the next election. This is what I came up with...
SNP - 53 seats
Labour - 52 seats
If Labour would be satisfied with that result, then by all means let them celebrate today. As Tony Blair memorably said about the Tories 'celebrating' their dismal results in the 1999 Scottish Parliament and Welsh Assembly elections - "The better they think these results are, the better it is for us."
In reality, of course, the above calculation almost certainly underestimates the SNP's true lead over Labour by a significant amount (and the opinion polls bear that out). As Professor John Curtice pointed out several times last night, by-election results are not an accurate guide to the national picture because incumbent governments almost always underperform in them. And that's before you take into account that this contest was fought against the highly unusual backdrop of the outgoing MSP having been convicted of domestic violence, and that Dunfermline is a particularly weak constituency for the SNP, where they had no history of parliamentary success prior to 2011 when they won an almost miraculous, wafer-thin victory off the back of Labour's national meltdown.
Marcia said it best on Wings last night - this by-election is the SNP's second-best ever result in the constituency.