your friend is at best an ignorant human being.
you cant apply an exact formula to the hsc, its not a science
"High ATAR = obsessive parents, selective schools, tutoring, illegal teaching practices"
for one, id say relaxed parents gets you a better ATAR. intrinsic motivation is greater than extrinsic motivation (i believe science supports this one)
selective schools, it would help, but by no means does that equate to a high ATAR
tutoring, the lazy-mans method of studying. (see that other tutoring thread)
illegal teaching practices, i dont know what this means, but based on the last few points, im sure i can find an argument against it. for example, if a teacher used the whip, it would be illegal, but certainly wouldnt guarantee a high atar.
you could also make a case in this way
"High ATAR = obsessive parents, selective schools, tutoring, illegal teaching practices"
is similar to saying
"relaxed parents, public schools, no tutoring, legal teaching practices = low ATAR"
and i think it is clear to see that the second equation is far from true
you could also disprove the argument by finding one person who had everything on the right hand side (obsessive parents, selective schools, tutoring, illegal teaching practices) but got a low atar, and im sure there have been a few of those
just so many ways to disprove