Bonsoir
"This is not the case (I have the data from UCAS)."
If you note my sentence included the word "here", ie what I have picked up from French who post on MN is that huge status is attached to which school and University you go to. French students now seem willing to consider the UK for tertiary education, but only if they get a place at one of a very small number of top Universities.
(Ironically I have heard the same the other way round from a London based French mum whose DS was determined to go somewhere Northern even though he was considered a strong Oxbridge candidate. He wanted to avoid being sucked into what can be quite parochial groups of Frenh students. The concern being that though French students may choose to study in the UK they often want to continue socialising with other Parisians.)
There also seems to be an assumption that the French Bac is treated somehow differently. I can't see why this would be. Top economics departments are focussed on their world standings and will want to recruit the best students they can. They will also have good experience of a range of different school graduation qualifications. Again the MN orthodoxy seems to be that the French education system is superior and that the French bac provides a better introduction to University than A levels. Academics will be spotting patterns and be wise to which groups of students might struggle. Certainly Cambridge has done a lot of work on their selection criteria and eventual outcomes and I assume Oxford has done the same.
We went through an economics application last year with DS (though selecting the more mathematical courses so Cambridge rather than Oxford E&M). Competition is huge and so though he was always a good candidate, advice was to apply to all four (Cambs, LSE, UCL and Warwick) with the hope of getting one. And treat it as a two year process so if you don't get anything first time round, get the best grades you can and apply again the following year. As it was he got one, LSE, first time round but knows others who got Warwick or UCL, or indeed Cambridge but not LSE and on a second application.
Each University will score based on their own criteria. Observation suggests that Cambridge may look for superb mathematicians, and those DS knew who got places first time round were international, and exceptional mathematicians probably strong enough to have gained places reading maths. Further observation suggests that Warwick, which has the biggest Erasmus programme in the UK, may like candidates who offer languages. LSE is very aware that it has problems attracting applications from state educatted British students from outside the M25, and that even if they do apply may take up places at Oxbridge or Warwick for financial reasons. Its all on the margin but my guess is that if you were a European student you might have comparative advantage at Warwick, whereas an applicant from northern England might fare better at LSE (and be able to keep the forlorn bloke running the Northern Society stall company during freshers week.) If you will interview well then obviously you might have a better shot at Oxford than at LSE, who dont interview and who have about 13 applicants for every economics place.
But unless you actually saw the scoring system you wouldn't know and there will be a whole heap of other variables. Its tough, but tough for Brits as well as Europeans or indeed anyone else. And pretty tough once you are there as well. People fail, and from what DS has seen, its not obviously those who have been through the British educaitonal system, or those with the weakest school grades. A levels seem to provide a perfectly adequet preparation.
So back to the beginning. Apply for the course that appeals most. Keep an open mind about courses away from Oxbridge. If necesscary treat it as a two year process. A good candidate should get a place somewhere, but its not easy, so grades, PS, school reference etc need to be tip top. Crying foul and blaming problems on some sort of British prejudice against the French Bac, or assuming that British Universities will recognise its obvious superiority, wont get a candidate very far.