The object of the exercise was a jocular trialogue between the comic, Paddy Ashdown and tame members of the electorate conducted at Church House in Westminster, live and under the glare of the media.
The problem was that some of the punters had not read the script. Neil Whinnerah, from the key seat of Southport, was the first up. His phone rang for some time. "He's not in," said Mr Cleese. Eventually Mr Whinnerah answered. "Oh hello," he said as if surprised.
The man from Southport said he had been meaning to become a member of the party for some time and that he had voted for no one else. What was it about the political broadcast - by John Cleese - which had persuaded him to tie the political knot? "To be quite honest, nothing," came the reply.
Mr Cleese then asked him what he had written in an impassioned postcard to the Liberal Democrats. "Can't remember."
Mr Ashdown prompted him that he had written on his concerns about the environment. "Did I?" was his reply.
The Liberal Democrats have always insisted that they wanted to inject a spot of fun into the election campaign, but was this what they had in mind?
Mr Ashdown kept reminding Mr Whinnerah that the press was present. Members of the media seemed to be shaking uncontrollably during the phone link, apparently in mirth.
At one stage the increasingly tetchy Liberal Democrat leader chided the new member for failing to discern that he had taken over the telephone. "I thought I was still talking to John," said Mr Whinnerah. "Surely you can tell the difference between our voices," said Mr Ashdown.
Then the untutored punter began to hold forth on unleaded petrol causing cancer. "Where did you get that from then?" said Mr Ashdown for whom the issue of carcinogenic fuel came out of the blue.
Margaret Heath, of Cumbria, was breathlessly supportive of the humorous approach espoused by the Liberal Democrats. "I think we should laugh at ourselves a bit more," she said.
Taking the conversation to a higher plain, Mr Cleese volunteered that he has once interviewed the Dali Lama. "He said that when people laugh it loosens up their thinking."
The former member of Monty Python's Flying Circus began to loosen up himself when Brin Dimmot, from Basingstoke, came on the line. "Is your name an anagram?" he teased. "It's genuine, it's me," came the reply.Reuse content