I KNOW they get a bad name, but let’s start with some experts. On Tuesday, after Nicola Sturgeon published Scotland’s Place in Europe, her proposal to keep Scotland in the EU single market after a hard Brexit, there were a lot of them around.

One said the blueprint deserved impartial consideration but “undoubtedly raises a number of political and legal challenges”. Another called the ideas “workable” but with “significant practical challenges”.

Overcoming them would depend heavily on “whether the political will exists to bring this about, within the EU, in the EFTA [European Free Trade Association] states, and most notably within the UK Government”. A third said a bespoke Scottish deal “depends crucially on the UK Government’s willingness to consider the whole range of options within … the UK’s negotiating position”. In other words, it might just work, but only if everyone puts in an heroic shift on behalf of Scotland.

The experts were the former European Court of Justice judge Professor Sir David Edward, former EFTA insider Sebastian Remoy, and Fabian Zuleeg of the European Policy Centre. All of their quotes were in a Scottish Government press release. Sir David and Dr Zuleeg are also members of the First Minister’s Standing Council on Europe, and as such helped inform the proposals. Even those working with Ms Sturgeon recognise the plan is an uphill struggle.

Credit where it is due, however. The paper was detailed, thorough and, without hyperbole, laid out what a complex mess Brexit will be. Ms Sturgeon clearly stated her goal. She wants the entire UK to stay in the single market and possibly the customs union. If not, then she wants Scotland to be in the single market, Norway-style, to safeguard economic interests.

That would mean the continued free movement of people, goods, capital and services, but not, she reckons, a hard border. If Theresa May blanks her demands, there’s always the possibility of another vote on independence.

At 62 pages, it’s far from encyclopaedic, but at least it’s out there, a visible plan for Scotland while the Prime Minister keeps her thoughts cloaked. But it also feels a strange, fragile thing, unsuited to the real world. As her experts point out, it requires a huge amount of political goodwill, if not altruism, to work. But where is it? Forget Spain’s vehement opposition to anything that could inspire Catalan separatists, and think simply of the UK Government.

A Scotland-only deal would require the UK to go into Brexit negotiations with the EU27 and sacrifice a slew of other demands to secure a devilishly complicated side arrangement for eight per cent of its population. Could Mrs May sell that to her party? After all, as Ms Sturgeon often claims, the Tories have been “hijacked” by right-wing MPs who already come out in hives at mention of the Barnett formula.

Would they stomach compromises on Brexit to give Scottish businesses “a comparative advantage relative to businesses in the rest of the UK”?

There’s also the First Minister’s pledge to keep campaigning for independence even if she secures a deal. “Why would I lift a finger for such insatiable ingrates and undermine my own position?” Mrs May might wonder; because, Ms Sturgeon would no doubt reply, the Union is at stake if you don’t.

Well, perhaps. Research after the 1997 referendum found support for Scottish devolution was linked to the popularity of the parties advocating it. The messenger mattered as well as the message.

In June, all five Holyrood parties had a Remain message, while only Ukip, with very little presence here, backed Leave. The 62-38 vote Ms Sturgeon seems to be pinning her hopes on in the event of a second referendum is probably more to do with support for the Remain parties than the electorate’s abiding love of the EU.

Small wonder senior SNP figures such as Kenny MacAskill are warning against yoking a Yes vote to Europe; time to “unharness” the two, he said this week. Immigration, the dog that didn’t bark in 2014, would also be deafening in a second referendum. Most Scots wanted a tougher immigration policy two years ago while the SNP wanted a more relaxed one.

Better Together thought about pushing the issue but held back. If independence was pitched as a means to avoid a hard Brexit, and thus maintain free movement of people, immigration would be as central to the next campaign as currency was to the last.

Ms Sturgeon has a proposal to keep Scotland in the single market. What she needs for Christmas is a guide on how to dodge a referendum if you paint yourself into a corner.