Bogdanor was completely and utterly wrong, but to be fair he was only wrong because he was making a basic assumption that was very widely held at the time - namely that the Conservatives were unable and unwilling to enter into coalition with the Liberal Democrats. As it turned out (only a few hours later), the Tory leadership were actually even keener on coalition than the Lib Dems were, for a number of good reasons -
* They feared, in Norman Lamont's famous phrase, being "in office but not in power". Compromise with the Lib Dems and the prospect of getting at least most of the Tory manifesto implemented was preferable to treading water for an unknown period as a minority government and getting nothing of any substance done.
* A weak Tory minority government could have become unpopular very quickly, and if they had been forced to call an early general election, there was a risk of being defeated by a Labour party which would by then have had a chance to regroup and elect a new leader.
* Having the Lib Dems inside the government, rather than offering limited support from outside, meant that there would be more than one party taking the blame for unpopular decisions. Indeed, there was a chance that the Lib Dems might end up taking more than their fair share of the blame.
* Adding on a ready-made "liberal wing" to his government appealed to Cameron in some ways - it meant that he would be at the ideological centre of the administration.
Now let's try and imagine what would happen next May if the arithmetic works out as we hope, and Labour's only chance of cobbling together a governing majority is to do a deal with the SNP that delivers Devo Max, or at the very least something much closer to Devo Max than the Smith Commission has proposed. As has been well-established, the SNP would prefer that deal to be a confidence-and-supply arrangement, rather than a coalition. But what would Labour prefer? I doubt if even they know the answer to that question yet, because they're still in denial about the very real prospect of the SNP taking most of their Scottish seats. But when and if that reality hits home, it's not impossible that they might come to the same conclusion that Cameron did in 2010, meaning that they would take the experts by surprise and press hard for full coalition with the hated Nats.
Confidence-and-supply might be of limited appeal to Labour, because even if it was a firm deal that was guaranteed for a full parliament, it would leave them with the "in office but not in power" problem - especially given that the SNP would continue abstaining on England-only votes. If Labour were going to make big and painful concessions to the SNP, it might only be worth it if they were sure of being able to win parliamentary votes consistently for five years, or four, or three, or however long the agreement is proposed to last.
Or perhaps they detest the SNP and the whole idea of Scottish self-government so much that they would refuse to do a deal at all, no matter what the cost? Maybe, but they would be fully aware that the potential cost could be very substantial indeed. If the Tories feared in 2010 that a Prime Minister Cameron at the head of a weak minority government might lose an early general election after six months, the mind boggles as to what Labour think would happen to a Prime Minister Miliband in similar circumstances.
And what about the other side of the equation - would the SNP be willing to accept the painful sacrifices that would be required to enter into formal coalition? Like the Lib Dems, they would be risking deep unpopularity as the junior coalition partner, and would also have to deal with the awkwardness of dispensing with their long-held position of not voting on England-only matters. But IF the coalition agreement contained a cast-iron guarantee of Devo Max within a short timescale, my guess is that any amount of pain would be worth accepting. To borrow Alex Salmond's phrase from the referendum campaign : "it's an opportunity that may not come our way again".
So on the day that Mr Salmond confirms he'll be seeking to return to Westminster, it's worth pondering the irony that his return might lead to him to become Deputy Prime Minister of the UK - and that if it does happen, it may well be at Labour's specific request.