it would be pointless for durham to reject oxbridge candidates, because they would lose masses of their best intake. if you are interested in studying at oxbridge with the collegiate system and everything that goes with it then durham would also appea to you, so they'l be lots of people applying to both.
there could always be an option of makign durham like oxbridge in as much as you can only apply to one. but it would involve lots of clever marketing. they might lose some of their best people, but I reckon it would just get a name for being a northern cambridge. it would be less scary than applying to oxbridge. i think they should do 100% interviews too.
i do marketing for a living. maybe they should employ me to do it! although i think that sachi and sachi would be a bit better at it