It would indeed be neat if there were a simple Yes-No question on independence but the world is not neat, politics seldom tidy.  The one reason why some significant extension of devolved powers should be on the agenda, and on the ballot, is because it’s clear that there is a strong popular mood which wants precisely that. 
Now, of course, a majority vote for independence in a one-question ballot would rule out ‘devo-max’ or whatever such an option is ultimately called.  In theory of course a majority against independence should leave ‘devo-max’ as a possible option.  The reality is that with the exception of one scenario, a No-vote on independence would kill ‘devo-max’ stone dead.
Cameron and the Tories are unhappy enough with a referendum on independence which they believe they might win but will not tolerate a referendum they might lose.  The very thought of referendums gives the Tory leadership nightmares.  Their own English back-benchers and constituency activists have their sights set on a referendum on what, for them, are far bigger issues, Europe and the Euro, a referendum on which would tear the Tory Party asunder.  While moreover the Tories may be in favour of a pared-down state in respect of economic policies, the unified, powerful and essentially conservative nature of the British parliamentary state machine is at the heart of Conservative ideology.  Their historic adherence to the concept of parliamentary sovereignty and the diminution of parliamentary power inherent in popular referendums sit uneasily together.
The Labour Party has quite different reasons for opposing ‘devo-max’.  If all fiscal and economic powers were devolved by Westminster to Holyrood, the case for Scotland’s Westminster MPs having a vote on only defence and foreign policy issues would be unanswerable.  Effective Labour majorities, and therefore Governments, at Westminster would be rare.
There is also a certain irony in the Labour Party’s insistence on a straight one-question referendum.  They claim they want a clear answer, which can only be given to a single, clear question.  Perhaps consistency is not a virtue to be expected of politicians but Labour’s 1999 referendum asked precisely two questions, one on the principle of devolution and one on tax raising powers.
The reason why controlling the questions is crucial however becomes even clearer if there are to be three options.
One approach would be that the first question poses status quo against more power to the Scottish parliament and the second question, only to be counted if ‘more power’ beats status quo, being ‘independence’ or ‘devo-max’.  Such a formula best suits the pro-union, devo-max supporters.  There aren’t many of them in powerful places.  It’s therefore an unlikely scenario.
Approach number two is that the first question poses independence against maintenance of the union, with the second question, only to be counted if ‘maintenance of the union’ defeats ‘independence’, being  ‘devo-max’ or status quo.  Such a formula best suits the nationalists.  If Westminster controls the ballot, it is also therefore an unlikely scenario.
There is also a third approach, so far scarcely mentioned, a single transferrable vote: one ballot, three options (status quo, devo-max, independence).  Vote 1-2-3.  My guess is that with that approach the bookies would be offering 100-1 on that devo-max would win easily since many electors would favour devo-max and most of both the pro-independence electorate and the pro-status quo electorate would mark it as their second choice.
There is also a variant on that third option, STV with four options, the fourth being status quo ante, back to one unified parliament for the United Kingdom.  My old friend Tam Dalyell would vote for that.  Any remaining unreconstructed unionists who believe, like Tam, that devolution must inevitably lead to separation and that separation is a bad thing would vote for it. Logically it should be on the ballot.  The reason it won’t be is that no-one is demanding it.  Even the Scottish Tories, who opposed devolution, now endorse it.  There is no meaningful support for this most logical (if retrogressive) of positions.  That speaks volumes about how devolution has changed the substance of Scottish politics and the mind-set of the vast majority of Scots.
It is also indicative of the reason why most of the leading members of all of the unionist parties fear devo-max.  By impelling the further consolidation of the Scottishness of politics north of the Tweed, it keeps independence on the agenda and ultimately, perhaps not in my lifetime, makes it a likely outcome.
I stated earlier that with the exception of one scenario, a No-vote on independence in a one-question referendum would kill ‘devo-max’ stone dead.  The one exception is a No-vote victory by a very narrow margin.  If the status quo triumphed by say 51% to 49% and Devo-max had not been on offer, Scotland would waken up with a feeling similar to that felt after the Cunningham 40% rule negated the first devolution referendum, cheated.
The Labour Party would split with the devo-maxists lining up alongside, or at least close to, the SNP and the Greens.  The next Holyrood election would see the SNP and new allies returned, likely with a huge majority and with a mandate to create what the lack of a third option had destroyed.   However one judges the political nous of Cameron, Clegg et al, they would not permit that scenario.  The British ruling elite has long learned to trim its sails when that saves the boat from capsizing.  The devo-max option they least want debated today, would be their first choice then and it would be given to the Scottish people without any need for the niceties of a further referendum.
This article was first published in The Scottish Review on 19 January 2012: http://www.scottishreview.net/AlexWood219.shtml