Teams now have a week to add the finishing touches to their boats and American's Cup Event Authority chief executive Sir Russell Coutts believes there is still plenty of improvement to be had before teams fulfill their potential.
"We had some practice racing over the past week and it's been pretty interesting, including a collision between Emirates Team New Zealand and Land Rover BAR," observed Coutts, who steered Team New Zealand to victory in 1995 and then a successful defence in 2000, before lifting it with Alinghi in 2003.
"You're going to get more and more of that as the boats get closer and closer, and the crews are pushing them harder and harder. It's a natural thing that will happen and hopefully not too much.
"There were several standout performance this last week, in my view. Softbank Team Japan have made a big gain, but things are changing every week.
"Essentially, every time the teams bring out new technology or learn new techniques, it's a game changer often. The learning curve is still pretty steep, but the skill that these guys are sailing at and racing at has got to be seen to be believed - it's incredible."
Team New Zealand open their challenger series against Team France next Saturday, before a highly anticipated meeting with defenders Oracle Team USA on Sunday and then what now looms as a grudge match against BAR later that day.
NZ Herald's Dana Johannsen will be on the ground in Bermuda, covering the America's Cup for NZME, and you can catch live blogging of races, featuring former Team New Zealand weather strategist Mark Orams, on nzherald.co.nz.