So why pick Cooper? The undoubted fourth ranked option and a man whose worst nights have come at Eden Park.
A man who has been subjected to the most intense scrutiny from both the All Blacks and New Zealand public and wilted each and every time.
There's talent aplenty within Cooper - but it's talent that has counted for precisely nothing over the years as he's mentally imploded when he's faced the All Blacks.
But presumably his past explains the present. If Cooper is to be considered a genuine option to go to the World Cup, he needs to prove he can play under pressure. And could there be a more intimidating environment for him than Eden Park with the Wallabies one draw away from taking back the Bledisloe Cup?
Is there a tougher assignment in world rugby than facing the All Blacks in Auckland and it would seem that Cheika wants to throw Cooper into the cauldron to see what happens.
Australia, after all, have the toughest World Cup draw with England and Wales in their pool and what's the point in taking Cooper - anyone for that matter - if there is doubt they can perform in the biggest games.
Is picking Cooper to play the All Blacks at Eden Park any different to the All Blacks selecting Lima Sopoaga to play the Boks at Ellis Park?
It's the nature of World Cup year. Coaches need answers to questions they suspect will become relevant further down the track.
"They are in the same boat as us," said All Black coach Steve Hansen about the Wallabies.
"They have got to answer some questions for the World Cup. They have got the same restraints we have. They have five test matches so they have to make some decisions. World Cup year brings its quirks and you roll the dice."