I think what Kiraken is trying to say is that Sydney Tech (or fully selective schools outside of the top 15 in general) have potential to get or have gotten 99.95ers over the course of many years. Obviously it's near impossible for Tech or a fully selective school outside of the top 15 like Hurlstone or Girraween to like 5 99.95ers every year - that's insane consistency for top end results.
For the past 3 years at Tech:
- 2011: Dux got 99.90
- 2012: 3 99.95ers
- 2013: Dux got 99.95
Clearly, the top Tech students (top 15ish) can get 99+ and a few hitting 99.90s and 99.95s over the years.
And don't correlate SCHOOL RANKINGS with TOP END RESULTS (e.g. 99.95ers or 99+).
School rankings looks at DA (Band 6 conversion) so the school as a whole rather than the amount of high-end students. Band 6 conversion is the next closest thing to average ATAR when it comes to accurately determining fair school ranks - you should look at the overall performance of a school rather than just looking at its top end students.
In 2011, Tech was like ranked 23rd with 0 99.95ers while in 2012, Tech was ranked 33rd with THREE 99.95ers. In 2013, Tech was ranked 32nd with 1 99.95er. So, in the year we got a few .95ers, the school was ranked lower compared to the years where we got 0 or 1 99.95er.
A good hypothetical situation, a school where all the students got 90 exactly in all their subjects would be 1st (100% DA, which will beat Ruse who usually gets around 70% DA) yet their highest ATAR may only be 99.00 (for example). While Ruse could get like 8 99.95ers or something yet be 2nd cause their DA conversion was lower.
As for your comment on Tech having half of the cohort being strong and half of the cohort being weak, it might be true or it might not be true. All depends on the year. Then again, when it comes to being relative, all schools will have a stronger and a weaker part of the cohort. The school with a smaller tail will most likely produce more band 6s and hence, end up with a higher school ranking. And yes, consistency does play a big role.
What I really want to place emphasis on (Kiraken probably has mentioned this before) is that - the top end students of most schools (regardless of their ranking or previous years' average ATAR) can do equally as well as each other.
The very top students of Sydney Tech, Girraween, Hurlstone, St George Girls, etc. may very well be as good as (or close to) the very top students of NSG, NSB, Sydney Boys, Sydney Girls, etc.
Obviously, the top 10 schools will produce more ''top students'' but that doesn't stop students from schools outside of the top 10 from achieving 99.90 or 99.95. Heck, you can achieve 99.95 at a rank 500 school with the right subjects, the strong marks and being 1st in all your subjects.
On another note, while many of you might argue that the PARTIAL SELECTIVE SCHOOL model does not work - we should look at Sefton High for example. In 2013, they cracked into the top 40 (i.e. being higher ranked than fully selective schools like Girraween and Penrith iirc) and was like only 4 ranks away from Sydney Tech. It has the potential to work and if its economically feasible, they might as well do it. There's many fully selective school alternatives out there for students such as Sydney Boys, Sydney Girls, Hornsby Girls, Ruse, Baulko, etc.