Just over a year ago, and unbeknownst to most of us who live on the banks of the upper Forth, glamour-lad and former football personality David Beckham dropped by the corner of Clackmannanshire where I live and entertained the workers at the Diageo whisky works and cooperage with his merry badinage.

I imagine. He was there as part of his involvement with the relaunching of the Haig whisky brand, under the Haig Club banner, and you may have seen the resulting advertisements, which look a little like a contemporary, more grown-up take on a Wham! video.

These glossy widescreen productions were created in a bonded warehouse Diageo happened to have lying empty at the time, of which there are many round our way, and which I had always naively assumed were always brimful of the good stuff. You would not know this to watch the ads, of course, because all the makers of movie magic really need when they are not working on location is a big empty shed in which to keep their equipment out of the weather, there to build their set and point their lenses. In the debate about the correct location for a putative Scottish film studio it has been pointed out by the Glasgow lobby that, for example, the interior of the Edinburgh flat where most of the action of Shallow Grave takes place was constructed in a warehouse in Glasgow. Although how that makes any case against the Pentland consortium's proposal for a private development at Straiton I am less than clear.

But, as any film-making in Scotland, from Shallow Grave to the Beckham Haig Club advert, makes clear, when there is a requirement for a large space in which to work, production managers seem to manage source one for the time they need to occupy it. The idea that creating a bespoke studio facility will automatically attract more film-making to Scotland seems to me flawed, or at least in need of considerable evidential support. Lottery money has helped create a wonderful network of venues for theatre companies to tour to in Scotland, but, as Christine Hamilton's review of theatre provision for Creative Scotland made clear, there is a lack of product for them to affordably programme. Film and TV insiders giving evidence to Holyrood's economy committee this week seemed to believe that the mere existence of a studio would be enough to combat the competition from Ireland, where producers from Braveheart to Game of Thrones have chosen to work.

Although there is some money on the table with a "film studio" label attached, the contention that it is the lack of a coherent strategy involving the arts quango, Scottish Enterprise and the government also seems spurious. A much more serious obstacle is the knowledge of the fate of Spain's Ciudad de la Luz (City of Light) in Alicante, which was deemed to have contravened EU regulations on state aid. Answering a Parliamentary Question from Labour's Jackie Baillie the day before the committee met, culture minister Fiona Hyslop was clear on the challenge: "A robust case would have to be made which demonstrates that any investment will achieve a commercially acceptable return."

In the absence of that, a privately-funded initiative like the Pentland Studios looks like the industry's only option, and if it is to happen in Glasgow instead it will not be from the pocket of the tax-payer.