The rumour from a work colleague who has just returned from San Fran, The reason Oracle have improved so much in the last 2 weeks. Is that when we were trashing them , Oracle got to see our foils, while the NZ boat was being taken out of the water, Oracle saw what the difference in the foils and Ellison immediately order new foils designed and improved and built at over $2m for a set.
They can change foils to meet the conditions of the day... hence why Oracle foil faster at the start (even when they don't a good one) and foil in a low breeze where NZ can't at the moment.
I think this has already been posted here but oh well