HEARD the one about the Scotsman and the Englishman and the BBC?

Let me set the scene; a Festival of Politics debate on whither culture and broadcasting in the constitutional debate. The Englishman, David Elstein, chairman of openDemocracy.net, and the Scotsman, James Boyle, chairman of the National Library of Scotland. Both, in previous incarnations, senior executives in broadcasting.

And here's the thing. Mr Elstein told his audience this was no time for timidity; now's the day and how's the hour to shake down the London-based BBC powerbrokers for a fairer return on the Scottish licence fee payments and to embrace the Scottish Broadcasting Commission's recommendation of a specific Scottish digital channel.

But Mr Boyle wanted more investment in ideas, product and technology and wasn't up for a Scotland-branded channel.

We should enter a small caveat at this point. Mr Elstein, who began his career at the BBC, went on to head up Channel 5 and Sky Programming has no little form in accusing the BBC of corporate complacency and being generally sclerotic.

Nevertheless he was right to embrace the cause of a digital channel for Scotland. People (though not Mr Boyle) who rubbish this notion have convinced themselves that the Made in Scotland label is handy shorthand for parochial programming.

At the moment, they have no shortage of evidence to pursue that prejudice. Radio Scotland is a shilpit shadow of the station which won the top Sony award in Mr Boyle's day. And an audience at the Book Festival supported the Beeb as the essential bedrock of public service broadcasting, but was disappointed in BBC Scotland in terms of reflecting back the nation it served.

This view is echoed in the BBC's own annual report, which found fewer than half of Scots listeners and viewers were happy with the news and current affairs output.

But the conclusion to be drawn from that is not that Scotland is full of second-rate programme makers or bereft of ideas merchants. What they lack is a sufficiently robust local market place in which to pitch their wares.

The investment in Pacific Quay, welcome as it was, has provided a base camp for a range of pre-existing network programmes like Waterloo Road and Mrs Brown's Boys, but comparatively spasmodic opportunities for homegrown commissions.

UK network shows bring investment and employment, but they don't help sustain the conditions for a critical mass of creatives that a channel dedicated to Scottish-made programmes could.

In the last three weeks the London radio caravan rolled into Edinburgh, setting up its temporary studios in Potter Row. And for a moment or two the Scottish capital was shunted centre stage. It's one of the nicer jollies of the year for the southern troops as they get to come up and have a few drinks and a few laughs with the same friends in different hostelries and maybe even catch a few shows while they're at it.

But periodic window-dressing doesn't alter the fact that post-devolution a huge chunk of network news has no locus in Scotland, whilst some pretty vital Scottish debates have a struggle to elbow their way on to the network stage.

The most common set of brackets around UK news broadcasts are those telling us the policy announcement/research finding/exam results/bank holiday only pertains to England or England and Wales. Scots-born London-based broadcasters such as Jim Naughtie, who has bought a home in Edinburgh and will augment the Good Morning Scotland team part-time next year, understand the intensity and importance of the debate the Scottish family is having with itself. But most of his colleagues, cruising around the Book Festival, TV Festival, International Festival and Fringe this month, seem to have just stumbled on the news that there is an up­- c­oming referendum which isn't about the EU.

The devolution settlement altered the terms of the broadcasting debate for all time, but left broadcasting decision-making as a reserved matter. Reserved to a London power base so convinced it is the centre of the universe that members of staff took a fit of the vapours and a redundancy package rather than move to the wilds of Salford.