'The Great British Bake Off' hired script writers because Noel Fielding and Sandi Toksvig "were not funny enough".
The show re-launched on its new Channel 4 home earlier this week but bosses needed the help of comedy writing team Dawson Bros to ensure the presenters - who replaced Mel Giedroyc and Sue Perkins - created plenty of "laughs", because there wasn't enough "natural chemistry" between the new co-hosts.
An insider said: "There just wasn't the right natural chemistry between them and it was decided there weren't enough laughs either.
"It's hugely embarrassing for Noel and Sandi, but the producers and Channel 4 were determined for the show to be perfect and didn't want to take any chances."
Sources close to Love Productions confirmed Dawson Bros - made up of brothers Steve and Andrew Dawson and their friend Tim Inman - worked on the programme, but insisted producers wanted to use Noel and Sandi's material "as much as possible".
An insider added to The Sun newspaper: "It's common industry practice to use writers and lots of TV shows do it.
"'Bake Off' brought some experienced people on board ahead of the relaunch to try out new ideas.
"But we wanted to use original material by Sandi and Noel as much as possible."
The show - which features judges Paul Hollywood and Prue Leith - launched with a peak viewership of 6.78 million on Tuesday (29.08.17) which will have no doubt pleased Channel 4 boss Jay Hunt, who recently admitted she would be "delighted" with such figures.
She said: "If it gets five, six or seven million viewers then I will be absolutely delighted. We've been very clear that this show can break even at Channel 4 at about three million."
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