rosequartz, I think history and the politics often have to come into play in a series such as WDYTUA. For instance in Brendan O'Carroll's case, it was probably necessary to give the viewer a synopsis of the political and social landscape of the time to understand how his grandfather's story slotted into it. I think I recall many episodes where the narrator went on to talk about the social history and Britain's foreign policy, particularly in episodes relating to those who traced ancestors overseas in former colonies.
Sometimes the focus is one generation only, I believe the first person ever featured was Bill Oddie. I didn't see it, but I gather it was about his mother only so he didn't go back very far.
I do agree that on occasions it is interesting to go back quite a long way and for some of the subjects something fascinating has been revealed on both sides. I remember Julia Sawahla had French Huguenots on her mother's side who fled persecution in France and a Palestinian grandmother on her father's side who started up and ran a hotel in Jordan. Boris Johnson's was also amazing in that respect, a Turkish great grandfather who was assassinated and something to do with a European royal house on the other side.
So many shows are formulaic and I guess WDYTUA is no exception which is why I imagine viewers get fed up after a while.
