There were plenty of reasons for optimism for the All Blacks after their demolition of the Wallabies in the Bledisloe Cup decider at Eden Park on Saturday night - but fans of the holders would be well advised to keep their feet on the ground.

This result was not quite the statement of supremacy that it might appear because there were three huge influences that will not play so big a part at the World Cup.

The first was home advantage. Eden Park does weird things to the opposition and referees. The All Blacks this year have been poor in Samoa, poor in South Africa and poor in Australia. Like the Black Caps they are a great at home, but have a bit to prove on the road. Not much, just a bit.

The second influence was the Australian playmakers. Quade Cooper was awful. He threw away possession, lost three high balls and attracted a yellow card which New Zealand cashed in for three tries. Matt Toomua coughed up two tries with a couple of awful kicks and Nic White gave away another by chucking a forward pass across his goal line.

The third influence was Nigel Owens. Australia have every right to complain about his performance. Twice in the opening half an hour Conrad Smith played the catcher when he was in the air. The absence of a yellow card beggared belief.

On Saturday Retallick and Woodcock assaulted players with cheap shots. In the lead-up to the turnover that led to the All Blacks opening try, Read pulled Will Skelton down and out of a driving maul on one side and Richie McCaw lifted Wycliff Palu's leg on the other side, the same offence for which Romain Poite yellow carded Rob Simmons a few months ago. Not even a penalty.

Regretfully I have to accuse Owens of unintentional bias. When McCaw asked for clarification of a decision, Owens said, "I'll have a look at the next one, okay." When Moore asked, he was told, "Back you go." Aaron Smith queried a decision and Owens apologised that there was nothing he could do about it. Moments later Moore wondered and was again told, "Off you go." Tone.

The All Blacks are quite good enough without the ref. Saturday's performance was encouraging but far from definitive. It will take much more to win three big matches away from home in a World Cup.

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