Withers said the questionnaire had been answered this year on the basis it was not constructed in a way that applied to state-owned enterprises.
"There was no intention to answer inappropriately, that comes from the board of directors down. The last thing we want to do is to obfuscate - it was unfortunate that became a focus for 15 minutes in what is an important hour for that committee's interaction with the board," she said.
"If I had regrets there were other things that I think it would have been worthwhile for the board to talk about and the committee to ask questions about and that didn't get covered."
She said she's not surprised at the focus on MRP.
"It was inevitable that the first of the companies to go through the MOM process would attract a high level of attention."
She left high school with School Certificate for a job as a bank teller at the BNZ in Papatoetoe and went on to become chief executive of Fairfax Media before taking top board roles at Auckland International Airport and Mighty River Power in 2009. She is also deputy chair of TVNZ and will from the middle of the year become an ANZ director.
She's prepared for the limelight.
"When you get appointed to these roles, if you're a chair of a company or a CEO - anything can happen at any stage that is going to catapult you into the public eye and you've got to be prepared to live with that."
Milford Asset Management fund manager Brian Gaynor rates Withers as one of the best company chairs around. She could talk candidly with a wide range of shareholders without giving away inside information.
"I wish we had more chairpeople like her, I rate her very highly."
He said she was expert in building boards with a range of talent and expertise that she could rely on as chair.
Gaynor said her involvement in Feltex as a director was "in the background" but she left the company well before it collapsed and had raised concerns about its performance ahead of leaving.
Withers' pet hate in corporate life is arrogance, which she does say is waning.
"What I've learned in my career is that arrogance tends to be a pre-indicator of disaster. I cannot countenance arrogance, nobody is entitled to be arrogant - we've all got things to learn and I think that one of the most rewarding things about being a chair or a director is sitting around and listening and coming to a view after a good vigorous debate."
Given her top roles, she is inevitably seen as a leader in the gender equality push and is part of the 25 per cent Group, a group of leaders who have banded together in a bid to boost the number of publicly listed companies with women on their boards to 25 per cent by the end of 2015.
She is also a big supporter of an aspiring directors programme aimed at "increasing the gene pool" of boards.
Withers knew MRP was going to make her life extremely busy. She's parked commitments such as public speaking.
"But it's only for a few months - we'll be out the other side of this in a few months and I'm really enjoying the learning."
After 16 years on the airport board she's stepping down later this year but has no other board roles in her sights.
"I don't want get over-committed, I'm very comfortable with my portfolio."
She and husband Brian have just celebrated their 40th wedding anniversary, and they became grandparents last year.
To clear her head, she goes horse riding.
"I just feel I was incredibly lucky. My parents emigrated [from Britain] when I was five and New Zealand has offered wonderful opportunities."
Joan Withers
Married to Brian with one adult son.
McAuley High School, a Catholic girls' school, Otahuhu.
MBA Auckland University 1989-1990.
Current board roles:
Chairwoman, Auckland International Airport.
Chairwoman, Mighty River Power.
Deputy chairwoman, Television New Zealand.
Set to join the board of ANZ.
Past roles
On boards of Meridian Energy, Feltex, The Warehouse, Tourism Holdings, John Fairfax & Sons.
Former chief executive of Radio New Zealand Commercial and Fairfax Media New Zealand.
