Oh dear, what a difference a day makes. You make anecdotal observations, I look at Oxford's own numbers. I invite them to show data, any data, that will contradict the observation I just made. Are those applicants who fell in love with Christ Church significantly weaker than those who gained offers elsewhere? I mention a phrase "all things being equal" - are they equal?
if they are significantly weaker, isn't that interesting in itself? Do you, by choosing a particular college, knowingly put yourself in company of people who may as well not bother applying?