I profoundly disagree with you that 'Starmer went to an ordinary school'. You are judging his school by the standards of today's egalitarian system, where everyone has an equal opportunity and no-one is in competition with anyone else; marks are neutral, such as, 'A', 'B', or 'C', etc. It is a sociological fact that the type of school Starmer frequented was indeed highly elite. There would have been intense competition for such a place, it was a door opener; pupils were pitted in competition with each other; actual marks and ranks were read out in front of the class. Those with good marks were encouraged to feel pride (hence the reputation of being 'stuck up'), with those of lesser ability expected to feel envious and ashamed, and to strive to emulate the more academic. For Starmer to get into Oxford to study Law tells you that behind those boyish spectacles is a determined character who had a good school support network, given subjects like Law and English are amongst the most popular and heavily oversubscribed.
Look up the social history of the tripartite system to confirm for yourself it was not only highly elite and sought after, it was indeed a ladder into the establishment, with even fee-paying parents desperate to get a place (one reason the system was abolished) and academic success ranked higher than the traditional fee-paying schools. It gave us Harold Wilson, Ted Heath, Margaret Thatcher, etcetera.
Claiming Starmer's Reigate Grammar of the 1970's was just 'an ordinary school' like the comprehensive down the road is a common misconception.
As for the rent boy joke, the caricature of the English upper classes as being effete is founded on a perception of 'camp' as being a peculiarly English thing. Like all caricatures there is a kernel of truth, given the the tradition of single sex schools.
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