The final HSC mark is made up of TWO marks - your exam mark and your moderated school assessment mark.
You always keep your exam mark so no matter how well or badly you do in the internals half your marks are the final exam mark. Hence a bottom ranked student who really studies hard can get a high exam mark, which they keep but they are also penalised for not working to their potential throughout the year. The same goes for the consistent worker who slacks off knowing they have done a lot of work but they can't be bothered over the last few weeks or so so get penalised with a lower exam mark, in all likelihood.
Your school assessment mark is moderated by the BOS using the total and range of exam marks earned by the school in the exam. The exam marks set the top and bottom of the range and the total exam marks earnt by the cohort are the total available to be allocated for the assessment marks.
Once the moderated mark and the external marks are determined they are average to give you your final HSC mark.
The system is fair, if assessment marks are to be included. The moderation is to stop teachers sending in the whole class with a mark of 100 and it allows students to showcase other skills they might have besides exam based skills.
