I know it’s a crudely constructed piece of history more designed for Hollywood than Holyrood but I love Braveheart. My favourite part is when the Scots are assembled at Stirling Bridge itching to get into battle and William ‘Mel’ Wallace instructs them to ‘hold…hold….hold…’ before unleashing the weaponry that would lead to victory. Our approach to a second referendum has to be a bit like that and we must be patient and like ‘Mel’ strike at the optimum time for success.

There is only one consideration that concerns and interests me when it comes to the timing of another independence and that is – is now the right time, and if we hold it are we certain of victory? It would be unthinkable to lose another indyref and almost reckless to proceed without good evidence it could be won.

Three and a half years on from the last referendum support for independence remains defiantly at 45% for with 55% against. Some polls show a greater support for independence, some show it lower, but Inevitably the numbers coalesce around these now almost iconic figures. This is both reassuring and disappointing. Reassuring that the vote for independence remains pretty solid three years on but disappointing that even with the prospect of Brexit there is no evidence of a pick up of support. Intriguingly, support for a second independence referendum also consistently ranks lower than support for independence itself and we should try to understand what this tell us about optimal timing. We also have to acknowledge that we lost 21 MPs last year where opposition to an early referendum was ‘at least’ a feature.

How do we then get over the line and win? Well, I don’t believe that it is in simply offering the same perspective that lost us the last referendum. We need a new independence offering that reflects the Scotland we now live in and takes into account the new political environment that we inhabit. Most importantly it needs to be sufficiently persuasive to win over that section of our population that have hitherto been unconvinced.

There are those who suggest that there would be a pick up of support by simply calling a further referendum pointing to the experience of the last referendum when Yes was behind only to make up much of the ground in the campaign. I’m afraid that this is not a view I necessarily share. Scottish independence is now one of the most discussed issues in our nation. Before the last referendum independence was pretty much an abstract idea that most people hadn’t properly considered, now, most of our fellow Scots have pretty strong views on the subject. Offering the same prospectus, with the same arguments, is likely to produce the same result.

Then there is Brexit. Scotland didn’t vote for this disaster but it is coming our way and is a potential game changer in the prospects for independence. As Brexit hits incomes and living standards I have no doubt that the Scottish people will start to look with renewed interest at those constitutional lifeboats strapped aboard the doomed HMS Brexit UK. As Brexit hits we will want to get off this doomed liner and sail for the shores of sanity as quickly as possible. But people don’t feel that yet and Brexit is still something that is to be fully experienced. Even when we leave next March there is likely to be a transition period delaying the full impact of Brexit trauma.

Then there is the question of the mandate. In this Parliament we do have a mandate to hold another referendum and if we begin to see evidence that the time is right it should be deployed . But we only ‘should’ hold a referendum when we are certain of winning and not hold one just because we ‘can’. If the optimum conditions are assessed to be found on the other side of a Scottish election then we should properly prepare and ensure that a mandate is once again forcefully renewed, undisputed and incontrovertible. I actually believe that it would be impossible to win a referendum if we can’t secure a mandate to hold one.

Then there are events. It is not beyond possibility that the UK Brexit project will totally implode in chaos and the ‘optimum’ time comes into play sooner rather than later. We should obviously grab that opportunity and quickly put in place a referendum. But with this scenario we’re literally talking about months and is therefore something we can not properly plan for and would be largely out of our control.

Scotland will secure its independence and we are so tantalisingly close, but we have work to do in convincing our fellow Scots who voted No last time to join us as well as uniting all Scots from both sides of the EU referendum. Setting a roadmap and plan is essential in getting us there as is striking at the optimum time for success.