Why does Downton Abbey need Aviva?

Peter Rhodes writes: Given that Downton Abbey is the most successful costume drama for years, why does it have to be "sponsored" by Aviva?

The insurance company's dismal real-life drama about a customer called Gary was sprinkled through the ad breaks in Sunday's episode like toenail cuttings in a tub of yoghurt.

The show actually began as Gary vanished into a bend on his motorbike. There was a bang, the camera moved in and someone was lying face down in the mud of the Somme, 1916.

That's how seamless, and utterly crass, was the fusion of Aviva commercial and quality drama.

Pointless, too. If Aviva is trying to wrap itself in Downton's solidly British values, it obviously thinks we have forgotten that it used to be called Norwich Union.

The company dropped this fine old English name to create "a truly global brand".