Working with a sports psychologist has strengthened their understanding on and off the water. Because they approach things in different ways, the key is being able to trust each other. It's also crucial that they are open and honest with one another.
Having clear set roles is critical to their ongoing success - including a silver medal at this year's world championships - and both women have distinct jobs to do on and off the boat.
Here's an example. At sea, one of them is focused on making the boat cut through the water fast as possible, while the other is dedicated to tactics, picking a course through wind, waves and rival boats. Their roles typically change when they switch from upwind to downwind.
Situations can alter in a flash on the water, but Team Jolly can call on the advantage of experience. They've been through so many scenarios in their collective sailing histories, they react almost instinctively to a sudden change.
Sailing as a pair means "you always have someone watching your back and supporting you," Powrie says. In a sailing partnership, the cycle of feedback is so much quicker; they're constantly bouncing ideas off each other, sharing critiques of their performances.
A decent amount of physical strength is needed in the 470 - a boat not renowned for its speed. Both Powrie and Aleh spend hours in the gym and on the boat building up their full and upper body strength.
They approach racing with a huge amount of physical intensity - making the most of every wind shift and swell to give themselves an edge over their competitors.
Aleh was inspired to sail after watching Sir Peter Blake and Sir Russell Coutts guide Team New Zealand to victory in the 1995 America's Cup. She had never sailed before, but she was driven to take lessons, join a yacht club, and get a dinghy. She's never looked back.
"I love sailing because everything's different. It's always a new challenge. I love being out on the water - especially in a country as beautiful as New Zealand," she says.
"Sometimes I forget that I might be inspiring others, but I'm always in awe of the impact our success has on other people. It's great when you bump into someone on the street and they tell you what effect we've had on them."