The reason that Oracle had their crazy comeback and beat NZ from an 8-1 deficit is that Oracle figured out how to foil upwind. While NZ had an entire 72 foot hull dragging in the water, Oracle was flying (not 100% of the time but they started pointing lower to go faster to fly generally) with 2 ft of hull dragging in the water (the foils). As a result, both boats were even downwind, but Oracle smoked them upwind every time.
No they didn't figure out how to foil upwind they fitted the self tacking jib. In other words they cheated.
Which is why ETNZ are now taking legal action. Word is out that there's an insider willing to spill the beans. Watch this space. Everyone knows it's to good to be true to be on 8 match points & getting flogged to winning every race & now doing the flogging
The Racing Rules on the matter are very clear RRS42 Propulsion states: A yacht shall compete only by using the wind and water to increase, maintain or decrease her speed. Her crew may adjust the trim of the wing, sails, rudders, daggerboards and hulls, and perform other acts of seamanship.
The vital words are at the opening of the second sentence 'her crew' - meaning that an automated adjustment which works independently of crew intervention is illegal.
Get your facts straight. Kiwis have self tacking jib on their boat as well.