Scottish independence referendum - a compromise

The 2014 Scottish Independence Referendum resulted in a fairly clear "No" vote - 55% No to 44% Yes - but with the recent hilarity of the 2019 UK election result and a very strong Scottish Nationalist showing, there are increasingly strident calls from the Scottish Nationalist Party (SNP) for a re-run.

Inconveniently, the SNP wrote a manifesto for the 2014 referendum in which they promised:

If we vote No, Scotland stands still. A once in a generation opportunity to follow a different path, and choose a new and better direction for our nation, is lost.
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The debate we are engaged in as a nation is about the future of all of us lucky enough to live in this diverse and vibrant country. It is a rare and precious moment in the history of Scotland – a once in a generation opportunity to chart a better way.
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It is the view of the current Scottish Government that a referendum is a once-in-a-generation opportunity. This means that only a majority vote for Yes in 2014 would give certainty that Scotland will be independent.

A "generation" is somewhere between 18 and 30 years (age of adulthood vs average age for first time birth in the UK) so it seems a bit problematic to hold a second referendum before 2032 at the very earliest.

Fear not, First Minister Sturgeon! Hemiposterical has a solution.

The eligibility to vote for the 2014 referendum was:

• British citizens who were resident in Scotland;
• Citizens of other Commonwealth countries who were resident in Scotland;
• Citizens of other European Union countries who were resident in Scotland;
• Members of the House of Lords who were resident in Scotland;
• Service/Crown personnel serving in the UK or overseas in the British Armed Forces or with Her Majesty's Government who were registered to vote in Scotland.

Let's flip that around by replacing "Scotland" with "England". Hold a binding referendum on Scottish independence, based on these eligibility criteria in 2023 (9 years after the first referendum, 9 years before the earliest date of the next one) and, if the population of England votes "Yes", wave a cheery farewell to Scotland.

This doesn't disenfranchise the Scots - they retain the right to hold their own referendum in the future and see it pass. It just additionally enfranchises the population in the part of the Union who have to fund Scotland to the tune of an additional £12bn per year, or so, in Barnett Formula payments. Since we had a referendum on EU membership with a similar net payment, this seems proportionate.

I'm not including Northern Ireland and Wales in the referendum in fairness to the Scots - they already receive significant Barnett payment, and so would be highly motivated to vote "Yes", evict Scotland and benefit from a potentially larger pool of funding.

So Boris, Nicola - how about it?