Earl's defence counsel John Westgate said she was mistaken that they'd stopped to eat an icecream her husband had just bought her at Glenavy, in the deep south of Canterbury.
He told the court today she continued driving while the chocolate icecream dripped onto her clothing, and when she distractedly tried to clean herself up, she drove into oncoming traffic.
Mrs Hubbard repeatedly denied those claims today.
Mr Westgate also asked her if she remembered crashing into another vehicle the previous year and driving off.
Police gave her an infringement notice for crossing lanes illegally and hitting a car in May 2010, the court was told.
She told police she was getting round to coming forward over that crash but "didn't want Allan to find out".
But when asked if she remembered the incident today, Mrs Hubbard replied: "Certainly not."
It was only after a lengthy cross-examination by Mr Westgate that it triggered her memory of the event - although she denied hitting another car, or getting a ticket.
Mr Westgate said the incident - as well as another one in April 2011 when a motorist complained that she'd crossed a centre-line in Templeton, outside Christchurch, and nearly hit a bus - showed she had a history of "running away" from responsibility.
"I don't like driving through Templeton. I do find that a bit... difficult," she said.
Mrs Hubbard was adamant that she had stopped for 5-10 minutes to eat the icecream on a roadside verge shortly before the accident.
But she accepted that given police know what time Mr Hubbard brought the icecream - courtesy of CCTV footage - and what time the crash happened, it wouldn't have given her any time to stop for that length of time.
"Your memory has played a trick on you," Mr Westgate said.
One witness, Derek Gee, told of concerns over Earl's "erratic" driving shortly before the crash.
He said that in his rearview mirror, he saw Earl's red Holden Rodeo 4WD ute drift into the Hubbard's oncoming white Honda Jazz causing the crash.
Mr Hubbard's firm, Aorangi Securities was at the time being investigated by the Serious Fraud Office (SFO) and was placed in statutory management in June 2010, owing investors up to $100 million.
The SFO laid 50 charges against Mr Hubbard under the Crimes Act but those were dropped shortly after his death.
The trial before Judge Gary MacAskill continues tomorrow.