In my first column of 2014 I briefly referred to the two crucial issues on the referendum front upon which I looked for more clarity as the year progressed - preferably well before that crucial September date.

These two issues were first, the currency options for an independent Scotland and second, what would be on offer from the unionist parties by way of (as close to guaranteed as possible) further devolution in the event of a 'no' vote. These issues remain critical if we are to know what 'yes' and 'no' might mean. On the second there has been little new light cast; the currency question has generated a great deal of heat from the First Minister, Chancellor and others, but again only a modicum of light.

I have just had the undoubted pleasure of chairing a series of sessions at the David Hume Institute involving the Deputy First Minister and then the four leaders of the other parties represented at Holyrood - one speaker per week over five weeks in late January and early February. Willie Rennie for the LibDems made it clear that he was seeking, via Sir Menzies Campbell, cross party agreement (involving Westminster as well as Holyrood) on some model of Devo Max. It was less clear that Labour and Conservative leaders were ready to follow his lead. I still have hopes that we might know more as to what 'no' would mean, at least in terms of further financial devolution, before the September vote; but am not holding my breath.

There has been plenty of action on the currency front. Whatever one makes of the Chancellor's intervention, including his publication of the very stark advice from the Permanent Secretary to the Treasury, it looks to be time to consider, with a degree of care, the alternatives to a formal currency union.

These alternatives are basically threefold, with variations within each. One option would be to continue to use sterling but 'unofficially' - 'sterlingisation' in the ghastly jargon. The second is a new currency; and the third adopting the euro - an option only available in the medium term and hence needing to be approached via one of the other two options.

There are pros and cons of each. The major positive of informal use of sterling is that the exchange rate would be fixed with our (overwhelmingly) most important trading partner, holding down transaction costs and maintaining a key element of the status quo. However, that would be at the cost of yielding all influence over monetary policy, which would be set by the Bank of England on the basis of the interests of the rest of the UK alone. It would also remain to be seen how the financial markets would view such an arrangement, how credible and sustainable this was seen to be and hence what the 'cost' would be in terms of the price of borrowing and the requirement to keep the markets content by running a tight fiscal policy ship.

One other point, upon which legal advice is required, is that this option might well be incompatible with Scottish membership of the EU. Apparently this is the case with Montenegro, which uses the euro informally and has no independent central bank: a requirement for EU membership. (There are suggestions that this problem could be negotiated away.) It would also be critical as to how the arrangement was viewed by the Scottish financial sector, including the banks, and indeed others holding assets in Scotland. If they perceived a one way street on the currency risk front - ie formed the view that Scotland might be forced into a devaluation - then capital and corporate flight would emerge as a real and major risk.

An independent currency would involve the immediate costs related to establishing a new central bank and associated arrangements and institutions.

This new currency could in principle be pegged to sterling, thus avoiding transaction costs and maintaining stability in the trading regime. However, experience for small countries elsewhere - especially those heavily dependent upon one, inherently volatile, income stream (in our case oil and gas revenues) - suggests it would also be essential to run tight monetary and fiscal policies.

This would be especially the case while credibility was established but also thereafter. Again any uncertainty regarding the durability of a sterling peg would risk capital flight and heighten uncertainties in the financial sector (including Standard Life!) in particular.

However, in this instance constraints on policies would be imposed via the workings of the international markets rather than via policies of another government (the rest of the UK) - as would be the case in a currency union and (effectively) the 'sterlingisation' option.

What then of the euro? Events across the eurozone in recent years have dented the case for an independent Scotland's entry. But it must also be noted that Scotland would not immediately qualify. First, EU membership would be required (a debate into which I do not plan to enter!) but thereafter Scotland would need to satisfy the much maligned Maastricht Criteria. These include the requirement referred to above for an independent central bank and, in addition, tight limits upon overall debt to GDP and annual deficit to GDP ratios for the public finances.

It would take time and painful effort to fulfil these criteria; and given those recent eruptions it can be expected that the criteria would be strictly applied.

In sum, euro entry might be a possibility a few years ahead. Meantime the options outwith currency union are informal sterling use or an independent currency. Even from this superficial assessment both have pluses and minuses, and, most certainly, uncertainties. But if these are the options that would be on the table in the event of a 'yes' vote, then further objective and evidence-based examination has to be urgent and essential.

Jeremy Peat is director of the David Hume Institute