AIB's former chief economist John Beggs has taken issue with previous testimony to the banking inquiry from the ESRI's John Fitzgerald.
Mr Fitzgerald said Mr Beggs relayed to him AIB's concerns about stress testing and suggested the ESRI could carry out its own tests.
Mr Beggs said he never asked Mr Fitzgerald to carry out tests on behalf of AIB.
He said the impression had been given that AIB had concerns about the severity of stress testing as far back as 2005.
Mr Beggs said he had no knowledge of the board's opinion on that matter and had no reason to believe they had misgivings.
He said he spoke about concerns that the tests were too procedural at the meeting which he instigated.
Mr Beggs said he was promoted to the role of chief economist in 2011 and was not in that position in the run up to the bank crisis.
He was previously chief economist of Global Treasury.
Under questioning, he admitted there was no chief economist until he was given that role in 2011 but he said that did not make him the de facto chief economist before then despite his public profile.
The former chief economist of Ulster Bank said he was an outspoken advocate of a soft landing.
Pat McArdle said that in 2004 he warned that house prices could fall by 35%, he said he did not continue in this vein and he should have stepped up his warnings.
Bank of Ireland's former chief economist Dan McLaughlin said he had predicted that any correction in the housing market would involve flat or falling real prices rather than a fall in nominal prices.
Mr McLaughlin said he got it wrong, as did everyone else, but he insisted the fault lay with the massive contraction in the final quarter of 2008.
He said he never used the term "soft landing", and that he saw the house market slowing down but not at the scale it had done.
Ulster Bank lost €4bn in deposits after guarantee
Earlier, the inquiry heard that Ulster Bank lost €4 billion in deposits in the month following the introduction of the bank guarantee.
Robert Gallagher, former Ulster Bank Chief Executive Corporate Markets Division, said other institutions were proactive with their customer base in their desire to build deposits and reinforced their communication around the guarantee.
Ulster's parent Royal Bank of Scotland stepped in to provide extra funds.
They told former finance minister Brian Lenihan of their concerns about the impact of the guarantee at an event in their headquarters on the morning of 30 September, just hours after it had been introduced.
Ulster Bank was not part of the guarantee, it was later invited to join but declined as the terms were impossible.
Fine Gael's John Paul Phelan asked about the perception that Ulster Bank was the instigator of 100% mortgages.
Michael Torpey, former Group Finance Director, said it would have been better if they had not been introduced but he said he believed they were already available on a case by case basis from a number of institutions.
Socialist Party TD Joe Higgins referred to an inspection conducted by the Financial Regulator in 2005 which found 27% exceptions in the residential mortgage lending book.
He asked if there was a free for all in lending arising from pressure to extend the business.
Mr Torpey said the Financial Regulator did not engage with questions directly but wrote to the bank.
He said the lending exceptions were challenged by the board.
He said he was satisfied they operated in a highly controlled environment but Ulster Bank was not perfect.
Mr Torpey said they wanted to grow to match AIB and Bank of Ireland.
Mr Torpey said he got a termination payment of £1.2 million when he left in 2008.
Mr Gallagher said he got a notice payment which was a portion of his salary and was in the hundreds of thousands.
Mr Torpey said the Financial Regulator had a very formal approach and had a system where he made observations in writing.
He said if issues had been made directly, they might have been more quickly defused.
He said they recognised there were weaknesses and they were treated with the utmost seriousness.
