Idiot commentary over PMQs

I got to hear PMQs on the radio yesterday as I was travelling to go on a PE course at lunchtime. What struck me was how much the listener missed because of the patronising and self indulgent commentary of the BBC presenter talking over the top of it.

Rather than hearing the debate we got a constant interruption from a BBC man who explained that "Asking a question there about Lord Ashcroft" and "Jack Dromey is blah, blah blah" or "By William he means William Hague when he was Conservative Leader" or sometimes just waffle that could be said quickly in four words but was instead turned in to a 20 word sentence.

Why not treat the listener with some intelligence ? What not explain the subtle nuances after the debate has ended ? Why not just let is listen ?