"The only time that George Osborne comes to Scotland is to tell us what we can't do. Maybe that's an emotional statement, but it frustrates me that he's here to tell us what we can't have."
For Macdonald, chief executive of commercial property company Macdonald Estates and a leading light of the pro-independence Business for Scotland group, Thursday's unusually naked show of power dynamics offended fair play: "George Osborne is deliberately using a tactic to scare people into voting No, it's as simple as that. It's disappointing too that all the parties are [following suit]," he says.
"It's not constructive. It's forcing business leaders to say, 'We're scared now, if we can't have the co-operation of Westminster and the Bank of England on sharing currency, there's going to be problems ahead that affect my business so I'll have to vote No.'
"Reading between the lines of the newspaper reports you can tell the writers know it's a stunt being pulled and if Scotland voted Yes, they would have no option but to agree to some kind of shared currency.
"There are huge challenges ahead on currency, of course, and we are aware of that. But this just stops debate. I was at that lunch where [Bank of England governor] Mark Carney talked about the challenges of a currency union, but nobody left that lunch alarmed by his words. They suggested a way forward."
Among the eclectic group of business leaders who form the online-based Business For Scotland, Macdonald's views are among the most weighty. A high-profile figure, he is credited by many as having substantially increased the coherence and influence of Scotland's commercial property sector, through his work in establishing the first industry forum, now the Scottish Property Federation. His non-SNP affiliation bolsters the Yes team's claims to inclusiveness, although it is not unusual among Business for Scotland's 1300-plus claimed members.
A former board member of the centre-right think tank Reform Scotland and a proponent of a more federal UK, Macdonald was a passionate supporter of "devo max", pushed into the Yes camp by the absence of a devo max question on the independence ballot paper.
More generally, his status as last man standing among Scotland's high-profile property kings gives the Highlander's prognostications about the future of our economy some authority as well as interest.
So what, then, is Macdonald's preference if it turns out the UK parties' reluctance to create a sterling zone with an independent Scotland turns out to be sincere? Should there be a Plan B?
"Looking at what's happened so far - and I'm not siding with Alex Salmond or the SNP on this - they are in a position that they should not have a plan B because they are saying this is the plan, and it's commonsense to share currency, and that's how we go forward. I don't blame them for not having a plan B so far, but maybe it will be needed.
"I don't want an independent Scottish currency, I want to share the pound. But even if we had our own currency I don't see it as being detrimental to my business in terms of the continuity of what we do.
"In Scotland, we produce and will continue to produce [under independence] a property investment product that's attractive, not just to London-based institutions, but to worldwide institutions. So I'm not worried about that at all."
Is that because many of those investing in Macdonald Estates' projects are foreign currency users anyway? "Well, they are yes, but it tends to come through London. That's one of things that has to change."
I suggest that he would never go into even a minor business deal without considering how every potential niggling detail could go wrong. Given that he draws on business lessons for life, has he applied this process to considering Scottish independence?
"Fundamental to the approach I would take is to de-risk everything you possibly can, and that means the detail. But you can never de-risk everything. Great challenges will arise, like the question of currency has arisen, and there's a lot to sort out. But we can't have a perfect carpet laid out on to which we are going to step, no matter what."
Far more real a risk to him, as to other independence advocates, is the risk that the UK's "uniquely unequal" economy and society are set to implode, and that the recovery trumpeted by Osborne is illusory at best, with the monstrous UK debt level, which the Coalition has barely tamed, at £1.3 trillion and rising. Although he acknowledges that Scotland is a relatively prosperous part of the union, Macdonald's view of it is dystopian: an increasingly polarised society with communities in the poorest parts of the country struggling with "no stimulus and no industry".
"When you look at the speed that global change is taking place, it's just not on [for the UK] to adopt an attitude of, 'We're good at what we do and we're not going to change because we are the best at it.'
"There is a tendency to think, 'Don't change because there is nothing wrong with the way things are.' That it's not consistent with a development agenda that takes us forward. There are significant challenges out there, but you can take a more constructive approach to dealing with them when you are in control of your own destiny."
In keeping with his belief that, in life as in business, maximum devolution of responsibility gets the best results, Macdonald paints a compelling vision of a post-independence Scotland that rediscovers its inheritance of exemplary fiscal prudence that he agrees is not much in evidence in contemporary political discourse.
He envisions a culture change - not overnight, but eventually - into a more collaborative society. It's one in which business, politics and the third sector put the "polarisation" of recent decades behind us to pool our complementary skills, and in which Scots reintroduce ourselves and our wares to the world, which somehow doesn't associate us with the slave trade or aggressive imperialism. Macdonald sees no reason why we can't collaborate in industry like the Germans, and take pride in the achievements of our own wealthy businessmen like the Irish.
"My biggest fear is that after a No vote, we'd be dejected, rejected and the negative psyche that can exist in Scotland will be magnified. For that reason, without any hesitation, I will vote Yes, because it's the only way forward."
His vision of a more business-minded Scotland, where the national balance sheet becomes everyone's affair, is an inspiring one. The prerequisites are that a mass of people here vote Yes, and then learn to love rather than resent more business involvement in society. Both are tall orders, but if anyone can, Dan Macdonald can make you believe it can happen.