well...quite a debate this is turning out to be..
anyway.. i feel that the dear OP should not be overly criticised for pointing out a particular situation that is no doubt currently experienced by undergrads in oxbridge.. while some may take offense to the advice given, there are others who may actually find it useful..
clearly a large number of us feel strongly about academic rigour but we do not represent the entire world population and therefore it is likely that there are some who may find the workload of oxbridge overwhelming or the academic system not a right match for their style of studying.. hence, if at this point in time, they realise that oxbridge does not match their personality, they may well choose to go to another uni.. this is by no means a white flag as i believe that it is crucial to select a uni which will give u the opportunity to enjoy education, which is the primary essence of higher learning..
and with regard to the whole 2nd grade uni thing.. sigh... i would nvr judge a person based on the uni he/she attended.. only by their character..