Challenged about the continuing worries of the private sector, Purnell said: 'The proof of the pudding will be in the eating.' Indeed it will.
But the trouble is that this particular pudding will have to be consumed for at least the next 10 years.
And if the new BBC Trust should turn out to be very much like the governors, but operating under a different name, what exactly will the sanction be?
The government has an answer. If the BBC Trust doesn't behave in a truly independent way and address the BBC's impact on the market for digital services, it will find it tough securing a new Royal Charter in 2016.
Big deal. In a decade's time, all the trends toward a more personalised digital media should have played themselves out.
You can be sure that if the BBC is going to crowd other players out of the emerging mobile media market, or compete against the regional press by launching local television all over the place, the damage will surely have already been done.
In the meantime, we will have to rely on Ofcom's involvement in the market-impact assessments to provide that element of external independence, which will ensure that new services are not just nodded through, but are subjected to a proper process.
Yet Ofcom's potentially vital role, which has given some reassurance to critics of the governors, such as ITN and The Newspaper Society, appears to have emerged at least partly by accident.
Naturally, the BBC Trust would have much preferred to carry out its own market assessments. Who wouldn't? There was just one small problem: the BBC Trust is responsible only for the BBC and therefore had no statutory power to require outside bodies to hand over potentially sensitive commercial information.
So maybe Ofcom could just collect the information on behalf of the BBC Trust and then hand it over?
Not surprisingly, Ofcom chief executive Stephen Carter was not too amused at the prospect of doing the donkey-work for the BBC Trust without being given a role in return.
And so it was, last week, that Ofcom was licking its lips at the prospect of 'developing the co-regulatory relationship with the BBC'.
The residual traces of the regulatory turf war could be seen as the BBC tried to talk down Ofcom's role and instead emphasise that the assessments would be overseen by a joint steering group. This might involve independent members, as well as representatives of both Ofcom and the BBC. As Purnell said, the proof of the pudding ...
Which services are looked at will be as important as the decisions on the market assessments. Will the BBC's new video player, which will make available all the programmes broadcast by the Corporation over the previous week, be assessed? It looks like a new service, even though no new programmes are involved.
Channel 4, for example, believes fervently that such a development could have a profound impact on the market and therefore should be properly investigated. Yet will the BBC be free to just go ahead and do it? That is what it did with podcasting, which could one day begin to affect the market share, and therefore the revenues, of commercial radio.
It is up to Ofcom to ensure that some of the questions which will be hard for the BBC Trust to tackle are fully addressed.
As partners of the BBC in this relationship, the regulatory body would always be able to publish, or at least publicise, a dissenting voice if the BBC Trust were to be too accommodating to the BBC management. That could improve the pudding's taste.
30 SECONDS ON ... THE BBC
- The BBC's first charter came into force in 1927. The Charter Review, which examines the BBC's output, is carried out by the Department of Culture, Media and Sport every 10 years.
- The BBC is regulated by 12 governors appointed by the Queen, and run by an executive board of nine directors, appointed by the governors.
- The latest government White Paper proposes that for the next charter, the governors will be replaced by a BBC Trust, which will look after the expenditure of licence fees, and an executive board, handling day-to-day management.
- The government must determine the length and level of the next licence- fee agreement, which starts in April 2007. The BBC wants an annual rise of 2.3% above the rate of inflation until 2013 to help fund its 拢5.5bn broadband and on-demand services.
Source: BBC News.