There are some questions politicians prefer not to talk about if they can possibly avoid it.

One is: can Scotland’s policy of free university tuition really be sustained?

Aversion to this question can be summed up in two words – Nick Clegg – though student finance was of course hugely sensitive in Scotland long before the UK Lib Dems spectacularly U-turned on their 2010 election pledge not to raise fees.

In the early days of devolution, the Labour-Lib Dem Scottish Executive introduced a graduate endowment scheme which kept tuition free but asked graduates to make a one-off £2000 contribution to fund bursaries for students from disadvantaged backgrounds.

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The ideas was vilified by the SNP in opposition, who (unfairly) badged it a “backdoor tuition fee” and made abolishing it a totemic pledge.

Ever since then, and especially following the rise in tuition fees in England and Wales, free university tuition has been a high-profile devolution dividend, held up as one of the great benefits of living in Scotland.

Which indeed it is – though not one without difficulties attached. That headline generosity and egalitarianism comes at a cost – a financial cost and, some fear, a cost to certain would-be students.

Some £2,020 less is spent per head each year on Scottish student tuition than the amount available for English students taught at English universities, according to a report by the Institute of Fiscal Studies last month (though Scotland’s four-year courses mean overall funding per degree is slightly higher).

This difference underlines how challenging it is to meet the cost of free tuition from Scotland’s limited budget. And to help keep control of costs, the number of places available for Scottish students is itself restricted.

Those places are now to be cut by 1200, after the finance secretary Shona Robison announced that extra places created during the pandemic to accommodate the higher numbers of pupils achieving university entrance grades, would have to be cut back. This is a return to the status quo, according to the Scottish Government, and not a retreat.

But it sort of is. Long before anyone had heard of the novel coronavirus, there were anxieties about the restriction on numbers of funded places for Scottish students. If universities charge fees, as Scottish universities can with students from the rest of the UK or overseas, they need not restrict student numbers. But with Scottish students, universities get an allocation of Scottish Government-funded places.

The Herald: Nick Clegg with David CameronNick Clegg with David Cameron (Image: free)

Cutting funded places by 1200 will reignite fears about access to university for Scottish students, particularly if demand increases. Some parents also worry that with an important drive underway to widen access to university for children from deprived backgrounds, with targets attached, an unintended consequence might be that kids from better off backgrounds struggle more to get a university place. It’s not unusual to hear parents speculating about this, though firm evidence for it is hard to come by.

The Commissioner for Fair Access Prof John McKendrick, in a report two years ago, said that the new places created during the pandemic should be made permanent saying that to cut them back again would be to “undermine efforts to meet future access targets”.

He added: “As student demand is increasing, and projected to increase further, the failure to increase funded places would reactivate fears about applicants from more advantaged backgrounds being 'displaced'.”

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Well if competition for places did become tougher, perhaps people would just have to accept that as the price we pay for free tuition and widening access.

Alternatively, though, if demand is projected to increase then shouldn’t we be looking for ways of levering more cash into the system so the number of places for Scottish students were not solely dependent on the cash-strapped Scottish Government?

What are the options? Say you wanted to increase the number of places for Scottish students by 2000. Why does it have to be funded by full scale tuition fees or nothing at all?

Could you introduce a modest "parental contribution” based on ability to pay, on a sliding scale, to contribute towards fees alongside existing government funding?

Contributing according to your income is not a new idea in student finance (maintenance grants were means-tested) and the SNP makes a virtue of it in the tax system. You might design it so that no contribution were required below a certain income threshold and that the very most anyone paid was £1000 per year (and only for those at the top of the income scale).

That would compare very favourably with the £9000 a year students in England are expected to pay. I’ve no idea how much my back-of-the-envelope scheme would bring in to supplement the Scottish Government’s student funding but enough, perhaps, to sustain hundreds if not a thousand or two extra places for Scottish students.

But but but…there are obvious difficulties with this. The English experience suggests that once students and their families are asked to contribute, the numbers only go up. Even if the maximum contribution started at £1000 a year, how much would the Scottish Government have increased it by 10 or 15 years down the line?

Besides, the very mention of tuition fees gives politicians the heebee geebees. That’s why there’s a code of omerta about it among many politicians.

OK, so could you do more to encourage voluntary donations? In the US, there is a culture of lavish endowments of higher education by wealthy alumni, though it has tended to shore up the elitism of certain institutions.

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Could a donor scheme be set up operating centrally to support tuition funding at all Scottish higher education institutions, aimed at graduates? How much might that bring in? Embedding this culturally so that it were as normal for graduates to donate a few quid a month to a scheme like this as to Save the Children or the RSPB, might help.

An open and frank political debate about how free tuition is working in practice and how sustainable it is, is overdue. Scotland’s egalitarian system is a source of pride, and so it should be, but that doesn’t mean it’s perfect.