If the guests were surprised, the programme-makers are alarmed. 'The BBC is like a ghost-town,' said one senior drama producer. 'There is an indefinable mildew in the air.'
Something strange is going on at the BBC - and many people call it Producer Choice. Since 1 April, programme-makers in radio and television have been free to choose whether to use the BBC's internal production resources - studios, cameras, design, costumes - or whether to buy from the external market.
Seven weeks into the programme-making revolution, shock waves are still reverberating through the Corporation. Its success or otherwise will be crucial to the drive announced last week by Alan Yentob, Controller of BBC1, to improve the channel's ratings.
Critics at the Corporation, who will queue up for days to attack the system anonymously, say Producer Choice has resulted in more and more talented hands lying idle as BBC producers discover it is cheaper to go outside.
By contrast, champions of the new system say that, finally, programme-makers are responsible for the real cost of their programmes and that the licence payer is getting value for money: 'I'm making better programmes,' said Lewis Bronze, editor of Blue Peter. 'So far I think it's working.'
The battle will be won or lost in what are now called Resource Business Units, which have been ordered to break even. Early evidence suggests that the Outside Broadcast and Design Departments have acquitted themselves well against predatory independent competition - but others, like the studios, are finding life more difficult.
Critics say the apprehension and fear over the new procedures mean that BBC staff are in danger of a mass nervous breakdown: 'Being on location these days is like being in therapy,' said Philippa Giles, a senior drama producer. 'Everyone in the crew is depressed about their prospects. Morale has never been so low.'
The case for the defence goes like this: any change - and this is one of the biggest in BBC history - is traumatic; trust the Director-General's judgement, and give it time to work.
But everyone agrees that more and more people are wandering the corridors of the Corporation with clip-boards and calculators. One head of department laments that while 6,000 jobs have been shed, he is now having to take people on to keep up with mountains of new paperwork.
'I'm having to expand the bureaucracy when I want to be hiring creative people.' He is certain senior management now recognises that a U-turn may be the order of the day: 'It's a joke.'
Margaret Salmon, director of personnel, admits to 'teething problems' but points out that some programme departments have bigger budgets than entire ITV companies. It is not surprising they are hiring financial help to control expenditure.
But Philippa Giles says that unless 'bulwarks' are built into Producer Choice to protect the Corporation's creative culture of studios, camera teams, design and costume departments, they will soon disappear. 'The best people are leaving already,' she said.
The new system is only seven weeks old, says the management, trying to look confident. But the staff are unconvinced.
'There is a fundamental problem which John Birt (the Director-General) and his acolytes will not admit,' said one senior producer in Factual Programmes. 'The economic logic of Producer Choice, to get departments competing to undercut each other, contradicts the BBC's stated desire to retain its talent base.'
The prophets of doom pronounce that if the BBC sacrifices its talent base on the altar of Producer Choice, hopes of catching ITV in the ratings will be in vain.
Captain Moonlight, page 23