Clive D. W. Feather wrote:
I've just got off a Northern Line train at Finchley Central, and was
bemused to hear it announced as "This train is for all stations to Mill
Hill East".

Technically correct, but ... where would you put intermediate stations?
Dollis Brook Viaduct occupies most of the space between the two.

That's nothing, I once announced that this train is all stations to
Olympia, while at Earls Court!