Every proud country has its trove of foundation myths, and Scotland is among the richest in national stories, from Robert Bruce's spider to Rob Roy, Flora MacDonald and Archie Gemmill in the 68th minute against Holland. But as yet no country, Scotland included, has rooted its national identity in the fiscal consequences of a dissolved monetary union – or any esoteric economic argument.

Standard Life, a pillar of the Scottish financial establishment, last week joined George Osborne and other London-based politicians in attempting to sway the Scottish electorate against independence with a warning over the volatility that would be unleashed by a vote to go it alone. The No campaign is a leaden mass of economic argument, backed by baroque thinktank papers and contributions from company bosses brave enough to put their heads above the parapet but who will be viewed as distant and hectoring by potential Yes voters.

Given that the financial sector accounts for around 13% of Scottish GDP – some £14bn a year – last week's contribution from Standard Life would have had a marked effect on any electorate that puts economic considerations first. The Edinburgh-based pensions group employs 5,000 people and is proud of its 189-year-old heritage, but warned: "If anything were to threaten this, we will take whatever action we consider necessary – including transferring parts of our operations from Scotland."'

On the same day, the studied neutrality of Royal Bank of Scotland was shattered when a sentence buried deep in its annual results stated that a Yes vote "would be likely to significantly impact the group's credit ratings and could also impact the fiscal, monetary, legal and regulatory landscape to which the group is subject".

If the economic argument against going it alone is to carry any purchase, then the interventions of Standard Life and RBS probably represent a high watermark for the hopes of the No camp, although Lloyds Banking Group, owner of the Bank of Scotland, is likely to have one last go when it releases its annual report this week. After that, the big private employers in Scotland which have yet to voice concerns – if they have any – are Tesco, Asda, Wm Morrison and FirstGroup.

For the No campaign, this week's words from Standard Life and RBS have to count. If swing voters will cast their ballot on whether they feel they will be £500 better or worse off under independence, then a big employer's threat to quit the country should have a tangible impact.

What hasn't worked so far are the monetary threats of George Osborne, the balanced but alarming economic analysis of Bank of England boss Mark Carney and the knottily compelling warnings from the National Institute of Economic and Social Research. In that trio of interventions alone, one might have thought there was enough intellectual heft to squash Alex Salmond's argument that Scotland can operate effectively as an independent economic entity. But many polls showed a narrowing of the No campaign's lead in the wake of Osborne's speech, which at the very least indicates what happens when you try to lecture a country with a world-class education system.

Scotland has the intellectual capital, the economy and the resources to operate as an independent country and the risk for Osborne, Nick Clegg and Ed Miliband is that the emotional pull of independence could be enhanced by a debate that resorts to the language of the footnote, the bar chart and the graph. The approach of Standard Life – the implicit threat of real jobs going south of the border – is their best hope.

Meantime, it is worth noting the quiet contribution of Standard & Poor's, hours after Standard Life said its piece. Its assessment of Scottish independence said that the challenge of going it alone is "significant, but not unsurpassable". To many Scots, that is an encouragement, not a warning.

New dotcom boom still doesn't add up

One thing was made abundantly clear last week: the dotcom boom is back.

New rules have applied to the huge valuations of internet businesses for some time now – from Twitter to Instagram and WhatsApp. They may generate little or no profit, or even sales, but it is all about potential and we are all in new territory with social media. Or so the argument goes.

But selling fridges and washing machines is a rather more down-to-earth business, even if the transactions are carried out online. As such, the valuation last week accorded to Appliances Online, or AO.com, is barely credible.

This business – sales last year £275m, bottom-line profits just £6.8m – was priced for flotation at £1.2bn. That's 175 times earnings and 4.5 times sales. Mad, eh?

But hold on. On its first day of trading, the shares shot up to value the company at more than £1.6bn – nearly six times sales and 235 times earnings. At that level it was being more highly valued than Home Retail Group – the owner of Argos and Homebase – which has more than 1,000 stores, a turnover north of £5.5bn and profits of £90m. It was, indeed valued only a smidgeon below Dixons and Carphone Warehouse.

AO.com and its advisers argue that it is expanding rapidly and is about to storm the German market. It may well be, but then its rivals may also fight back. And because the barriers to entry in online retailing are low, there could just be another AO.com coming along quite soon.

The fact is the investors chasing the shares are desperate to find the next Asos (whose shares, which were just 130p in 2007, are now more than £70 each) or Ocado (60p at the end of 2012 and 570p now). Three hundred institutions raced for a share allocation. But how many people paying into the pension funds those institutions were wagering would think it such a wise idea?

Don't forget small British films in rush for Oscar glory

If Gravity wins an Oscar tonight, it can be labelled a success for the British film industry. As the British Film Institute says, the space drama, starring Sandra Bullock, is "98% British", led by the wondrous special effects created by London-based Framestore. Film production was worth £1bn to the UK economy in 2013, up 14% on the previous year. It employs a pool of highly skilled professionals, from editors to special-effects whizzes, who maintain the UK's reputation as a reliable base for blockbuster production.

But there is a flipside to this. The number of independent British films has fallen, and funding for such movies fell by more than a third in 2013. Which means there's a growing discrepancy between the financial health of the British film industry and the cultural wealth it generates. Sex Lives of the Potato Men aside, let's see that £1bn produce more homegrown cinema.