a couple of years ago i saw an academic ranking of british universities.sheffield was the best with oxford and cambridge around 20th place.
so maybe you're right that oxford is different from yale
Example: http://www.arwu.org/rank/2007/ARWU2007_Top100.htm with Cambridge 4th, Oxford tenth and Sheffield in place 72, just ahead of the University of Arizona.
Something tells me it would have been better going to Sheffield than going to this local University just for this reason, but we all make mistakes.
As it happens, I became friendly with the head of computer science at my local University choice, for doing well in a computer trivia quiz.