Deans' Barbarians led at half-time but were not able to withstand an All Blacks second-half surge.
But the positive result could not paper over some glaring cracks in
the All Blacks' defence and Deans says they can be beaten due to the
fact that they do give chances to the opposition.
"They're giving teams a little sniff, they're giving teams encouragement," the former Crusaders and Wallabies coach told the Canberra Times.
"They gave us a fair amount of encouragement in the first half.
"The critical thing is where they go from here. I've got no doubt
they'll go that way (pointing up) because that's what they do. It means
too much to them."
Deans said that no other nation were able to keep winning as
consistently as the All Blacks while employing a squad rotation policy
like the one that they do.
However, he says Hansen is building a good squad and does believe the All Blacks will win the next World Cup.
"They're vulnerable but they're still travelling well, that's what they do," he said.
"The players have had a taste of it and they want more. They're hungry and they just bubble out at the top.
"They're in no hurry to give up their status as the best team in the world."
Meanwhile, Deans hailed Crusaders flyhalf Richie Mo'unga, who produced an impressive display for the Barbarians.
Mo'unga is one of five players who is joining the All Blacks squad in France.
The introduced group are likely to play in a match on November 14 against a France XV.
"He showed he's capable of playing at this level. And it will happen, it's quite simple," Deans said of Mo'unga.
"He'll get there and experiences like this accelerate that."