This is more of a comment than a question, but I find the A*A*A offers in science quite unfair - I am currently beginning to prepare for the ISA/EMPA practical exam part of my science A-levels, and the ISA exams are hugely affected by cheating across the country. This is not an opinion - it is acknowledged by teachers and students, and even AQA - who changed the time frame for sitting the exam because of it... but still left a window of weeks for the exam paper to be sat! Students can therefore discuss the papers with friends from nearby schools. The consequence of all this is that the grade boundaries are EXTREMELY high - without cheating it is practically impossible to get a good mark. I'm lucky enough that my school have chosen the EMPA exams this year, which are less prone to cheating - but what about students who are subject to exams with high grade boundaries due to cheating?
Quite apart from that, I've also had exam papers marked incorrectly despite remarks and appeals, when the answer for a 1 mark question is word perfectly that which is given on the mark scheme! In Maths A-level, I'm aware that alternative methods may not be credited if they are not detailed in the mark scheme, in spite of their total relevance and accuracy.
In light of all this, is it truly worth giving students such high offers when A*s are so unpredictable? Even aside from the cheating/unreliable marking, exams are at the end of the day somewhat dependent on chance - whilst my sister attained 3A*s in her humanities A levels, she could not have guaranteed any. I can accept that an A*AA offer would keep standards high, but why go through all of the interview process only to let people fall at a hurdle decided by chance?