The debate, some of which will be shown on Channel 4 tonight, was examining the issues raised by Potter's controversial lecture which opened the Edinburgh Television Festival on Friday. He had argued that the Birt/Hussey regime had led to demoralisation, hatred and bitterness.
But just as the debate was starting, Potter tested the cool of Sheena MacDonald, the television presenter, who was in the chair, turning to her as she introduced the session, saying: 'For God's sake get on with it. I have to say I don't feel very well this morning.'
The author of The Singing Detective and Pennies from Heaven, who has a skin disease, went on: 'My skin is getting flaky and my face might become like a Hammer horror film. It's up-chuck time.' Then as Ms MacDonald asked for a pause as the cameras got into position, he snapped: 'This is bloody incompetent.'
Asked about his denunciation of the BBC, he said: 'I did the whole damn thing on Friday . . . I don't want to go through it all again.'
Potter said the BBC management had caved in before the Government. 'People at the BBC are unhappy, confused and frightened. Hussey has to go. Birt has to go. I want someone at the BBC to stand up to the Government and say 'Make us. We'll take you on. You're a temporary political movement,' instead of standing up, hands in the air.'
In an increasingly heated debate Will Wyatt, managing director of BBC network television, said it was fantasy to think you could raise two fingers to the rest of the world, that the Government had legislated that 25 per cent of BBC programmes now had to be made by independent producers, that savings had to be made and that Potter was giving out 'a lot of abuse and no coherent argument'.
Earlier, Bob Phillis, BBC deputy director-general, implored staff to make their criticisms in private. He said the continual public knocking of the BBC was damaging it as it fought to retain the value of the licence fee and to have its charter renewed.