I've mentioned before (here and here) that the level of hyperbole in this general election campaign is getting a little silly on all sides. Sometimes this has become a story in its own right. Such was the case with Theresa May's claim in an interview with the Mail on Sunday that a post-election deal between the Labour Party and the Scottish National Party would provoke 'the biggest constitutional crisis since the abdication of Edward VIII'.
Now this is obviously over-the-top, and I'm disappointed that a politician of May's standing has clearly forgotten all about Gough Whitlam. (She must once have known about him; she was at Oxford University at the time of the Dismissal and surely even geography students were vaguely aware of what was happening in Australia.)
Nonetheless, there is a clear problem in the position adopted by the SNP. The party's manifesto is a mix (less charitably, a mess) of policies, some of which relate simply to Scotland, others to the whole of the United Kingdom.
So, for example, the SNP will 'seek an explicit exemption ... from the terms of the proposed Trans-Atlantic Trade and Investment Partnership' for Scottish Water. But not for Thames Water or any of the other suppliers. On the other hand, the very first page of the policy proposals (after the usual fatuous photographs of the leader) says that the party will 'vote for an increase in NHS spending across the UK of £24 billion by 2020-21'.
This seems to me to be at best impolite. Health is a devolved matter already, even without the additional shift of power to Holyrood that would presumably accompany the SNP having any say in the Westminster government. One doesn't have to accept the Conservative proposal of English votes for English laws to feel that a party with no candidates in England should not be announcing how much money they want to make England spend on its health service.
Nor, even if - as a voter in England - one believes in increased funding for the NHS, should one look to the SNP to deliver this.
Because it's not actually their business.
The manifesto of the Democratic Unionist Party, by contrast, has not a single word to say on the subject of the NHS, though it does mention the devolved health service. Instead the document is rooted entirely in the hope of a hung parliament, allowing 'an opportunity for Northern Ireland's voice to be heard in London like never before'.
The same bifocal approach runs through the whole of the SNP manifesto. The idea that the Scottish Parliament should be given the right to decide which sporting events are reserved for free-to-view television - that seems pleasingly parochial. Telling the rest of the UK how many houses we have to build is rude and wrong.
There is a constitutional issue here. Something to do with representation and taxation, since spending relies on taxes, whether now or in the future to pay today's borrowing.
And the problem is exacerbated by the voting system (which, incidentally, the SNP are proposing to scrap in favour of the Single Transferable Vote). The latest opinion poll, published yesterday, shows the SNP on 54 per cent in Scotland, which is predicted to translate into 96.5 per cent of Scottish seats.
Or, to put it another way, 1.3 million votes (assuming a similar turnout to last time) would yield 57 MPs. Meanwhile, as I've said before, Ukip - effectively the English equivalent of the SNP - will register over two-and-a-half times that vote for a total of maybe three MPs.
I don't think that, despite May's argument, the emergence of a minority Labour administration propped up by SNP votes will spark a constitutional crisis as such, since the rules of Parliament are perfectly clear about how governments are chosen by MPs. But it will provoke a crisis of confidence in the system of government. I don't know how that will manifest itself, but it cannot simply be wished away. Not in a country where there is already deep dissatisfaction with our version of representative democracy.
The answer, in the short term, can surely only be the introduction of proportional representation. The Lib Dems and Plaid Cymru, like the SNP, favour the Single Transferable Vote, while Ukip also support reform.
But whatever the outcome of this election - even if the Tories do get a majority in the Commons (a prediction to which I cling, despite all the evidence) - a reform of the voting system is an urgent necessity. It would be absurd to have another election fought like this.
Postscript: Since posting this three hours ago, a new poll has been published showing the SNP still on 54 per cent, but with Labour sliding still further - projections now suggest the SNP would win every seat in Scotland.