Firstly, I am not against it at all. I procrastinated away god knows how many hours doing it
But to be honest,
you will have a more accurate prediction of your scores than anyone here can give you if you have some understanding of the system:
From VCAA:
A study score shows how well you have performed in a study at Unit 3 and 4 level, compared to everybody else in Victoria who took that study. Study scores calculated by the VCAA will be used by the Victorian Tertiary Admissions Centre (VTAC) to calculate the ENTER.
The maximum study score is 50. Each year, and for every study, the mean study score is set at 30. A score of between 23 and 37 shows that you are in the middle range of students; a score of more than 38 indicates that you are in the top 15%.
For studies with large enrolments (1,000 or more):
* 2% of students will get a score on or above 45
* 9% of students will get a score on or above 40
* 26% of students will get a score on or above 35
* 53% of students will get a score on or above 30
* 78% of students will get a score on or above 25
* 93% of students will get a score on or above 20.
Now these percentages are fairly useless at the moment. What on earth does an A get me? B+? etc
This is where VCAA's published grade distributions come in handy.
http://www.vcaa.vic.edu.au/vce/statistics/2007/statssect3.html - 2007 stats
http://www.vcaa.vic.edu.au/vce/statistics/2008/midyear/midyear.html - 2008 mid year stats
They do change each year but within an individual subject, the percentage of people who get A+, A etc will stay roughly the same. So lets say if we did Business Management (simple as only one exam and alphabetically near the top), and we predict we will get B+ on the exam, this means that we are somewhere within the top 17-28%. This means that if we showed the same level of achievement in sacs (we didn't stuff around in school all day every day, conversely we weren't A+++++ student and flunked the exam) we can expect somewhere between 34 and 37 (roughly)
This is all well and good, except it is assuming your initial guess of your letter grades is accurate. I don't mean to break people's hearts but I see some people posting here with the belief that an A+ standard in their school is identical to an A+ standard within the state (or same for any other letter grade). You have a better idea of your school's past results than I do, if no one got 40+ last year for a subject and you are ranked 5th in your cohort and you are getting A+s internally you shouldn't be expecting 40+, or for your SACs to remain at A+. VCAA moderates your sac marks to ensure consistency between schools.
Predicting grades accurately is the greatest uncertainty in this process, and I don't want to see people setting themselves up for heart break for thinking they will do better than they will. Generally people make modest predictions and are pleasantly surprised however
This is why I am hesitant to predict scores for anyone else unless I know them very well, because if I know them I can see through any unrealistic predictions (both over and underpredicting)
And of course with hard work you can push your study scores up by a few points then what you're used to getting