But I think the ones who are very smart and confident in themselves do 10units, doing 4/5 subjects (these can include extensions) and they just focus on these subjects as other 'smart/intelligent' people do 12-14 units and work prob as hard as those already mentioned but 2-4 units do not actually count.  
I am considering dropping ancient history because my rank is not very good at all (13/24).  And in my other subjects I am doing pretty well (aiming for band 6s which is very likely looking at my rankings, so I am confident in my ability in 10units) But my teachers do not want me to drop down to 10.  And I do not understand why not?  If I stuff up one subject in the HSC and ancient history (if i keep 12) ends up counting, it scales really poorly and the UAI contribution score is really crap too.  And this would not help me.  
A lot of ppl are telling me that it is fine to do ten, some also say its living on the edge (but those are the deadshits).  I am still not 100% sure of what to do.  
FOr Currysauce, u are doing amazingly well and i think u must be putting a fair bit of effort in.  However some of this effort may be wasted because u are doing 12 units and 2 units will not count.  Having said this though, U are on target for 99+ definitely but i think u need to like the subjects u r doing, if u like them all keep them, if u dont, drop 1 
(and why do u do SOR?)