IT'S just over one month since Alex Salmond unveiled a large piece of sandstone outside Heriot-Watt University bearing his well-known prediction about tuition fees.

In doing so, he revealed not just a splendidly unmelted piece of rock, but also a startlingly loose grasp of the effects of policy over his period in government, not least the budget he and his Cabinet colleagues agreed for 2013-14.

After declaring that free tuition was now "a commitment writ in stane", he recalled that as someone "whose parents in an atmosphere of both free education and full grant, scrimped and saved to send four children to university, I know what a challenge and what would have happened with the imposition of large debt to people like myself".

Yet while Mr Salmond was First Minister, student borrowing in Scotland doubled in real terms, including for poorer students, while government spending on grants almost halved.

In Mr Salmond's day, a full grant was worth just over £5,000 at current prices. This year, the maximum grant, known since devolution as the Young Students' Bursary (YSB), is just £1,750. Students are expected to borrow the rest of their living cost support, meaning a loan of £5,750 each year if they want to take advantage of the Scottish government's "minimum income guarantee".

The budget for 2013-14 in particular marked a critical shift towards reliance on student loans to provide assistance with living costs. Between 2012-13 and 2013-14 alone, there was a 40 per cent reduction in the grant budget and annual student borrowing rose by 69 per cent. Scottish students are now taking out loans worth nearly £0.5 billion a year. For individuals, the most recent statistics show levels of borrowing which on average will mean a debt of over £20,000 for a standard four year degree. The figure is higher for those from poorer homes, who are also more likely to be borrowers.

The thresholds for grant have tightened, too, and where entitlements once gradually reduced, since last year they fall in sharp steps. Once household income reaches £17,000, YSB falls immediately to £1,000 a year. It is only £500 at £24,000 and above. None is payable once a household's income reaches £34,000.

Perhaps, in the spirit of science, someone at Heriot-Watt will propose a companion stone, providing the debt and grant figures from the beginning and end of Mr Salmond's tenure as First Minister. As well as the effects described above, that would show fewer students now benefitting from YSB than in 2006-07, even though claimants from other, now abolished, schemes have been moved into it and the total number of Scottish students has risen.

If the rocks will melt with the sun before Scotland introduces tuition fees, it seems equally possible that a' the seas will gang dry before the architects of Scotland's current system for student funding will acknowledge, perhaps even to themselves, that it is built on a rapidly growing amount of student debt. For degree students from poorer homes in Scotland, debt is still around half that faced by their equivalents in England, but very similar to what applies in Wales and Northern Ireland, and sometimes higher. Scotland is exceptional only in the way it expects student debt to be shouldered disproportionately by the poorest, because grant here is so low and thresholds so tight.

Before the 2007 election, Mr Salmond (and Nicola Sturgeon) made passionate speeches about their plans to "dump" student debt and replace it with grant. He described "£10, £15, £20,000 of student debt" as an "enormous debt burden". They may both be grateful that no-one at the time was inspired to commission a stonemason.

But here we are with Heriot-Watt's magnificent new monument and it surely deserves a name, so it can take its place amongst Scotland's growing collection of politically important rocks, real and metaphorical.

The Stone of Turning A Blind Eye To The Way Student Debt Has Doubled And Is Skewed Towards The Poor isn't very catchy.

Maybe it could just be the Stane O' Debt Denied, for short.

Lucy Hunter Blackburn is a freelance researcher specialising in student funding.