To be fair, a lot of people were fooled by Bert LLoyd, in his creating or "improving" traditional material. A lot of people try this, and fail, but it's incredibly difficult to write convincing trad songs.We all know the sort of thing, loads of songwriters write fake folk songs. Bert LLoyd was nearly unique in being able to do it totally convincingly. How many singers who do the ultra-trad Blacksmith spot that the great line about "with his good black billycock on" is pure LLoyd?
Alas, I missed the TV programme, so can't comment. Doubtless it will come round again. Or is there some "look again" facilty somewhere?