America's Cup: Secret of Oracle's miraculous burst of speed remains property of Team Ellison

What secrets lie under the waterline look to remain a mystery.

Oracle Team USA's secret weapon is still that - secret.

Attempts to loosen Oracle's tongues about the reason behind their sudden burst of speed failed yesterday.

In the after-race press conference both Oracle skipper Jimmy Spithill and syndicate boss Larry Ellison gave oblique answers to questions about their hidden weapon. Spithill's rambling answer concluded with the contention that "it wasn't any one thing", but a raft of small changes.

Ellison was more direct, saying: "You're going to have to figure it out for next time."

Before anyone interprets curiosity about this as sour grapes, know that Team New Zealand publicly maintain the stance that the Oracle amend ments to the boat were vetted by the measurement committee and are thus compliant with the rules.

However, there are still many unanswered questions about the improvements and, given that just about everyone figures the AC72s will not be a part of the next Cup, there seems little harm in letting even some vague facts be known.

Emirates Team NZ boss Grant Dalton said that the Kiwi boat was going faster than ever in the final days of the Cup match. But even those gains were not enough. Certainly Oracle's sudden leap from laggard to leader is unprecedented in the America's Cup.

Even accepting that the AC72s are a development class and that both crews have been highly vocal about the large gains that can be made as they learn to sail and re-mode the boats, Oracle's Cup-winning leap was one that can be called Beamon-esque - after US long jumper Bob Beamon who, at the 1968 Mexico Olympics, broke the world record by jumping 29 feet before anyone had even broken 28 feet. Most speculation centres on Oracle's automated foils system and/or the possibility that they have managed to find a way to include a gyro stabiliser or something similar.

Those systems could help explain why the Oracle boat has beaten the New Zealand boat in that it was quicker to foil, foiled more stably and for longer periods and put on bursts of speed that decided races.

On first glance such a system looks as if it would contravene the America's Cup rules that state that systems must be manually operated and not by stored power. But if the might of Oracle, US technology and vast resources of the fifth-richest man in the world have managed to find a way that their grinders can power such a system, that would mean that Oracle figured out a way to win the science-and-technology race that Team NZ led for so long in this Cup cycle.

"We have no way of being able to scrutinise or understand their systems," said Team NZ skipper Dean Barker last night. "We are basically in the hands of the measurers and we trust them to do a good job on scrutinising."