Details of this pilot are fairly vague as it was only ever reported in The Mirror (here).

Published April 21 2006 said that C4 were making The Jimmy Carr Show as a pilot and that “it will look back at the week’s events with comedy sketches and guests”.

In the first quarter of 2006 he had filmed 2 series of 8 Out of 10 Cats, for C4, and also The Friday Night Project in 2005.

It’s feasible that this pilot could have happened as, in November 2006, Chortle wrote an article about C4 Friday night’s schedule struggling for audience share (here).

In that piece they said that, the week prior, the Friday night 7p to 10.30pm slot had been the channels worst performance since Xmas 1998, with only 3.9% of audience share. With fingers being pointed at a Paddy McGuinness reality gameshow.

In May 2006, for example, 8 Out of 10 Cats was in the 9.30pm Friday night slot and that Chortle article says that it had 6% of audience share (alongside The Simpsons). Down from the C4 average of 9.9%.

I would assume that numbers had been dwindling for some time and that could have led to the channel greenlighting pilot shows.