In the good old days a television program, such as Doctor Who, would be board cast once a week for 30-45 minutes.

These days as soon as a program is successful spin offs and repeats are spread across the schedule to fill in as many gaps as possible.

Doctor who (45 mins) is shown on BBC1 then repeated twice during the week on BBC3
Doctor who Confidential (30 mins) once per week BBC3
Doctor Who Confidential (15 mins) twice per week on BBC3
Totally Doctor Who on (30 mins) BBC2 then repeated on CBBC

When you consider theres spins off Torchwood (45 mins) twice a week on BBC3 and the Sarah Jane adventures.

Who needs new ideas!