Thank you Novalis, I rather hoped you'd turn up and give a definitive answer!
Mollykins, in my opinion, once you get to the point of applying for "University", and if you get an interview then your performance at that interview is probably more important than the grades they request. If they want you the grade requirements might be very low. They will be asking within the panel, "Does this person have the qualities that we want at our University?" rather than if he/she can get the grades we need to take this applicant!
I'd appreciate an opinion from Novalis on this however!
As an amusing, but substantiating anecdote, a friend's son applied for a place at Oxbridge, at the interview he was asked "Why should we save the whales?". His answer was, "Because they are aesthetically pleasing." He got the place, with minimal grade requirements and went on to achieve a First!