It is hardly surprising. In cramped offices with newspaper headlines generated by the programme hung like trophies on the wall, Dimbleby and his team of researchers prepare for head-to-head interviews like a team of lawyers preparing a barrister for court battle.
For two weeks before Mr Ashdown entered London Weekend Television's studio they have been crawling over his speeches, policy statements, party manifesto and interviews.
But the first part of their battle is to get an interviewee at all. Alex Gardiner, the deputy editor, spends much of his time on the phone to spin doctors trying to "sell ice cubes to Eskimos", as he puts it.
Mr Gardiner sells Mr Dimbleby's two million audience and its status in Westminster as a proving ground for good performers, but it is getting harder: "Frost has been poisoning the well for all of us," said Edward Morgan, editor of the Dimbleby show. "Why should they do us if they can have an easy time on Frost?"
Many who come on Mr Dimbleby's two-year-old programme just try not to make a gaffe. Robin Cook and Malcolm Rifkind are favoured guests because they actually enjoy the cut and thrust of an argument.
The week before the show, Mr Dimbleby's team decide on an overall theme for the interview. Yesterday it was to test the impression Mr Ashdown gives of being a non-politician - of being the honest broker.
Mr Dimbleby does not negotiate the subject of the interviews. But he does undertake not to ambush a guest by discussing something out of their remit, otherwise they don't come back.
The day before the show Mr Dimbleby takes on three of his staff who role- play Mr Ashdown, trying to guess his responses. To one question, producer Andy Harrison makes a good stab at the "Ashdown anecdote": "I recently met a woman...". And, true to form, during the interview the Lib-Dem leader brings up a woman he met in Wirral to illustrate his point on tactical voting.
The role-play spent a lot of its time on how the Lib-Dem's 1p in the pound tax for education might be guaranteed to go to education. The programme's researchers had quotes from Charles Kennedy and others saying they believed in local democracy and the money would actually go where local authorities wanted it to - like care for the elderly.
Mr Ashdown denied this hotly and accused Mr Dimbleby of having poor researchers - instead of dragging in the audit commission as Mr Dimbleby had been briefed to expect, Mr Ashdown claimed an undertaking in the manifesto for a Lib-Dem government to force new money to be spent on education.
In the director's gallery a junior researcher was sent scurrying back to the production offices to find a copy of the manifesto to check this out.
Like all interviewers, Mr Dimbleby uses an ear piece, mainly so the director can tell him how much time is left. His predecessor in ITV's Sunday political slot, Brian Walden, used his ear piece to allow researchers to feed him questions. But by the time the manifesto arrives it is too late to brief Mr Dimbleby anyway, the show approaches its commercial break and the audience gets ready to ask questions.
"You see, I wrote our manifesto," says Mr Ashdown afterwards. "I spent 70 hours writing it and I know where the skeletons are hidden."
In the final analysis even Jonathan Dimbleby and his team haven't spent as long studying Mr Ashdown as Mr Ashdown has.Reuse content