Complex sentence: The show became one of Britain's breakthrough TV programmes, which kickstarted the careers of many rock and indie bands and created a popular TV show format, which others have copied while nowhere emulating the success of TFI Friday.
Split into simpler sentences: The show became one of Britain's breakthrough TV programmes, kickstarting the careers of many rock and indie bands. It also created a new approach to the popular TV show format, which others have copied, yet few have emulated the same success of TFI Friday.