APRIL is the cruellest month, TS Eliot said. But October’s looking pretty grim these days too. Besides the energy crisis, if you’re an SNP activist, there’s the UK Supreme Court to look forward to.

The day after the party’s conference in Aberdeen - its draft agenda full of bouncy ideas for campaigning in the referendum slated for 2023 - the Court starts hearing the case that could knock it on the head.

Last week, the Lord Advocate, Dorothy Bain QC, published the written case she intends to present on behalf of the Scottish Government. Nicola Sturgeon wants the Court to rule Holyrood has the power to hold Indyref2 under its devolved steam, meaning Westminster can’t block it.

However it’s also pretty clear she doesn’t trust the Lord Advocate to get it done. The day after Ms Bain’s written case was published, Ms Sturgeon made sure the SNP applied to the court to join the case to argue for the same outcome.

It’s an unprecedented state of affairs.

The Government’s top law officer, at the behest of the First Minister, has referred the question of whether Holyrood has the requisite power to the Court, saying it is in the public interest to get a definitive ruling on this “festering issue”.

In particular, Ms Bain has asked the justices to decide whether a draft Referendum Bill that would see Scots asked the “Should Scotland be an independent country?” question of 2014, would “relate to” matters reserved to Westminster, including the Union.

If they decide the Bill doesn’t, then Ms Sturgeon can have Indyref2 next year.

But if, as seems more likely, the Court decides it would trespass on Westminster turf, then the Bill will be junked.

In which case, Ms Sturgeon has said she’ll fight the 2014 general election as a ‘de facto referendum’ on the single issue of independence, and all those SNP conference plans go up in smoke.

It’s not hard to see why the SNP wants to intervene. The Lord Advocate’s written case is excruciatingly neutral from the party’s perspective, presenting both sides of the argument, and if anything giving more of a show to reasons why Holyrood can’t hold Indyref2 under its current powers, including the smoking gun of Donald Dewar saying so very clearly in the Commons as MPs were passing the law underpinning devolution.

Indeed, it’s difficult to detect Ms Bain advancing any kind of case at all in favour of the First Minister’s desired outcome.

This is also understandable. The matter is going to Court precisely because the Lord Advocate doesn’t know if Holyrood has the power to hold Indyref2 or not. She is “unlikely to have the necessary degree of confidence” to call it, she admits. So her reference is in effect saying: “I’m stuck here. Help me out. Tell me what to do.”

As part of that process, she has put forward arguments as to why Holyrood might have the power to fly solo, but they’re less than overwhelming.

They include saying a referendum asking folk their view on independence would have “nil” legal effect, while asking the Court to ignore the politics and stick narrowly to the law. The proposed Bill is “not directed at any particular outcome” and “relates to the Union in only an indirect or consequential way”. Oh aye.

She goes on: “Beyond the immediate effect of ascertaining the will of the people of Scotland, the practical effects of an advisory referendum are speculative. The court ought not to engage in such speculation because it is not equipped to do so.” But if the Court isn’t equipped to recognise the blindingly obvious, then I’m not sure what it is equipped for.

As the former Supreme Court justice Lord Sumption famously said: “Most law is only common sense with knobs on.”

If the Court were to ignore the common sense context, and the 1998 Scotland Act says it needs to consider “all the circumstances” when deciding if an issue is reserved, then it would make a fool of itself and the law. It’s hardly wild speculation that the Scottish Government is motivated by more than idle curiosity.

Ms Sturgeon is keen to remind people she was re-elected last year on a manifesto commitment to hold a referendum, and that same manifesto said: “The SNP is clear the referendum must be capable of bringing about independence.”

By intervening, the SNP can put forward its own punchier arguments, challenging the Court’s previous rigid view of Westminster sovereignty, and asking it to consider the right of self-determination recognised in international law.

It can also, bluntly, inject a bit of drama. Two days of overpaid eggheads pondering what “relates to” means isn’t the stuff democratic dreams are made of. And if - when - the SNP loses, it can weaponise the verdict by saying it has exposed the limitations of the British constitution.

But there’s also a risk an SNP intervention is unhelpful. As Roddy Dunlop QC, the Dean of the Faculty of Advocates, puts it: “It does have the potential to rather cut off at the knees the protestations that there’s no politics involved in the reference.”

The upshot could be First Minister Sturgeon using scarce taxpayers’ cash in the faint hope of getting a positive ruling from the Court, while SNP leader Sturgeon spends her members’ subs undermining that same process.

It would suggest the exercise was always about theatre, not substance, and the SNP’s opponents would make hay.

It’s a gamble that points to Ms Sturgeon reckoning she no longer has much to lose.

In late 2014, at the outset of leadership, Ms Sturgeon went on a strange, egotistical tour of the country’s stadia that saw her breathlessly likened to a rock star.

As she squares up to her political mortality with Indyref2 a forlorn hope, she seems to be coming full circle.

The Supreme Court case and general election look like the start and end points of an equally self-regarding farewell.

She departs the political stage as she arrived on it: empty-handed.