IT was back to the future this week at First Minister’s Questions.
I’m still trying to work out if the chamber was transported back to summer 2014 or projected forward to summer 2018.
No sooner had Nicola Sturgeon said on radio that autumn 2018 would be a ‘common sense’ date for a second referendum on independence than the other party leaders leapt into campaign mode.
Both Ruth Davidson and Kezia Dugdale pulled out the oil-figure lyrics from the old Better Together songbook and updated them for the possible upcoming reunion tour.
It was a key issue in the SNP and the Yes campaign failing to win the economic argument for independence in 2014, and after this week’s exchange, it is certain to be top of any No campaign strategy next year.
John Swinney was standing in for Nicola Sturgeon and his response was not to deal with the falling oil revenues or their impact on a newly-independent Scotland’s finances.
Instead, he took a similar approach to that used in the previous campaign.
Was oil a bonus, he was asked? Much like the answers given by Alex Salmond three years ago – that other countries would give their eye teeth to have a problem like North Sea oil to deal with – Mr Swinney said it was a “huge bonus” and began reeling off how many hundreds billions of pounds the UK has reaped in revenues over the last four decades.
Kezia Dugdale then told Mr Swinney that oil and gas actually cost the UK money last year, so low was the oil price.
Mr Swinney knew that, of course – as a former Finance Secretary he’s good with figures – but he decided not to talk about it.
Instead, he quickly cottoned on to the fact that both Labour and the Conservatives had adopted the same line of questioning at the weekly set piece, and decided to give the troops something to cheer.
“They’ve come back together again” he bellowed, " Like they'd never spent a moment apart" he goaded, hardly audible above the now raucous SNP backbenchers.
With Ms Sturgeon giving the strongest hint yet of an autumn 2018 referendum and the latest poll showing a 50/50 split on independence, it certainly looked like the campaign had got started.
In the exchange, there were lessons for both the SNP and Labour, however.
If the SNP is to convince a majority of Scots to vote for independence, the economic arguments, debt, currency and oil will have to be properly addressed.
Simply stating that of course we can use the pound, and trying to underplay the volatility of oil prices, won’t work.
Voters will need answers to the questions that they were not convinced on last time and there was no sign of those answers yesterday.
And for Labour, the question is can the party afford to be tarred with the same brush as the Tories, espousing the same arguments from the same platform?
The answer has to be no. Better Together was a disaster for Labour. 
If we are heading for a second referendum in 18 months, then some new strategies are urgently needed.
Both sides have lessons to learn.