Next month the 33-year-old hopes to bag a few more and lead the Black Ferns to a fifth successive global title when the tournament is held in France.
Twice a week she trains three times a day around her day job with the police.
"You have got to be organised to do it," she said, "but marrying the needs of my job and my rugby goals have forced me into it. Time management is one of the biggest skills I have learned.
"Lots of those skills transfer into my work with the police, you have got to be a leader and talk to people and I take those skills into my rugby."
There might be an early morning circuit training before work, a boxing session after work and then twice weekly rugby specific sessions with her Auckland Marist club. At other times there are weights, skills work and running.
At the gym she hits pads and concentrates on core work but never spars. Has she punched anyone in her main sport?
"I did a long time ago in my youth; I was getting picked on," she said.
Her fitness schedule is exhausting but the right diet and ambition drive Fa'amausili through the fatigue and the slog through Auckland's winter.
She used to be a postie but changed to the police force after the last World Cup.
Somewhere Fa'amausili has to find time to study for an exam before she travels to the World Cup and, on her return, she will spend a month in Wellington completing more exams.
"There's a fair amount on my wall planner and on my phone," she laughed.
"Training with the Black Ferns twice a week at the moment is great, then we do our own stuff on the other days."
Fa'amausili started at centre for her club, swapped to loose forward because she enjoyed the contact and has stayed in the forwards since. She still plays that role for Marist but when she turns out for Auckland and the Ferns it is at hooker.
At 1.63m and 77kg, she likes the technical and physical contest and says that has become even more pronounced with the new scrum laws.
For a long time she was deputy to former national skipper Farah Palmer, only getting chances when the captain was injured or subbed off late, like her debut against Australia in Barcelona for two minutes in the 2002 World Cup.
Old schoolmate Mealamu made his debut at the end of the same year against Wales in Cardiff.
"We had a reunion at Aorere College after the All Blacks won the World Cup and I do bump into him from time to time but he is pretty busy," Fa'amausili said.
And she's not?
If hard work counts the Black Ferns skipper is setting a torrid example for her Ferns teammates to emulate next month in France.