Thanks for pointing out that the QF SC discount, has even gone beyond directly competing routes.

For example, SIN/HEL only awards 120 SCs on AY, whereas QF handily point out that if they flew it then you would get between 160-175 depending on fare. I gather that is a penalty if you did not book the QF codeshare. While not a 50% reduction, it still as Dave points out, be very careful to use an SC calculator, as those extra flights to get say 40 SCs, may actually cost you.