Much to my surprise, I found the first episode of the new BBC series of Who Do You Think You Are? on YouTube.
He also discusses it on a BBC comedy show.
The episode was fun, not a lot of genealogical research though. Nobody pointed out that having Edward 1 as your 23-times great-grandfather means he is one (or more) of 16.7 million ancestors in that generation. It goes back to around 1300 when the population of Britain was around 3.5 million (with substantial uncertainty.) Lots of pedigree collapse. Likely anyone with a deep history in England could make a credible claim to be Widdicombe’s cousin.