"Those guys (Oracle) have got plenty of resource and plenty of power, and they can change things if they have to."
Listen: Brad Butterworth on the Mike Hosking Breakfast
The five days Oracle will have to analyse how the Americans replicate their feats of San Francisco four years ago will include sailing as well as technical refinements.
"I think the Team New Zealand, (Peter) Burling and Glenn Ashby, they're sailing their boat differently to the other guys," Butterworth said.
"Obviously they are sailing it better. But because everything is televised you can look right into the boats, how they are sailing, they'll be trying to learn something to help them lift their game."
Then there is the Jimmy Spithill factor, added Butterworth.
"He's an Aussie battler, that guy. Nothing is too hard for him," said Butterworth who was tactician onboard two Team NZ and two Alinghi America's Cup wins.
"But Burling has done a great job.....hopefully four more races."