The Devo Plus campaign, an offshoot of the Reform Scotland think-tank, has set out detailed plans for what it calls a "New Union", showing how the Liberal Democrat, Labour and Conservative parties could come together to sign up for firm proposals as a clear alternative to Alex Salmond's independence vision.
Campaign leader Jeremy Purvis, a former LibDem MSP, was flanked by both Reform Scotland founder Ben Thomson and former LibDem leader Tavish Scott as he outlined the proposals.
But while Labour's Duncan McNeil said he was there with the approval of his party leader Johann Lamont, and therefore brought some degree of commitment to consider the proposals, Conservative MSP Alex Fergusson was forced to concede that he was there in a personal capacity, placing a question mark over Tory commitment to the campaign north and south of the Border.
The report builds on previous Devo Plus proposals for increased tax-raising and benefits powers, demanding that Westminster sign away future rights over the existence of the Scottish Parliament and London's power to legislate in devolved areas. Mr Purvis said this package would then be signed up to by the three parties in the Better Together campaign, so that this would become the final "settled will" of Scots if they reject independence, ending the notion once put by former Welsh Secretary Ron Davies that devolution was "a process, not an event".
Mr Thomson said virtually all polls suggested a majority for enhanced devolution over the alternatives of independence or the status quo, adding: "We believe there is a point where devolution reaches its destination, with our plans for tax powers, benefits and now setting the Scottish Parliament in stone completing that journey."
Mr Purvis said: "This is a significant report that shows why and how agreement can be reached. We have shown that the most consistently popular way forward for Scotland is a Parliament with increased responsibilities within the United Kingdom.
"We are showing how a stable and sustainable way of delivering this can be achieved within the lifetime of the next UK Parliament before 2020. We have also shown with our suggested Statement of the New Union, how parties and others can come together with an agreed approach that the public will understand and be able to endorse."
Mr Purvis added: "We need to ensure that the public have a clear understanding of the consequence of their vote in 2014. Our report provides the basis for cross-party agreement to allow for that understating to be secured."
LibDem leader Willie Rennie said: "People want to be assured that No to independence doesn't mean no to change.
"I welcome Devo Plus's report and their call for all parties to come together in consensus for new powers before the referendum."
The SNP responded: "The inescapable fact of the matter is that despite the best intentions of the people involved in the Devo Plus group, the No parties are refusing to set out any vision of what Scotland would look like if they got their way in 2014."