Adding a fourth American Idol judge is a bad idea – like adding a fourth wheel to a tricycle, or a fourth leg to the injured dog that walks around hospitals on wheels sometimes.

Not to stretch that metaphor, but it would be fine if the fourth dog leg was as famous as the other three dog legs, but it’s not – it’s a weirdly anonymous dog leg that you wouldn’t even recognise if someone hacked it off and waved it around by itself away from all the other dog legs. Understand? Good.

Anyway. Kara DioGuardi, the new fourth American Idol judge, has now been formally introduced to the public. We could have just said that instead of banging on about dog legs and saved everyone a lot of time and confusion, we suppose. Oh, will we ever learn?