The IRFU has rejected suggestions it overstated the impact of moving designated games to free-to-air broadcasters would have on its finances.
An Oireachtas committee, established to examine Minister for Communications Eamon Ryan's proposals to designate certain sport fixtures as free-to-air, was told that the IRFU's figures might not add up.
The IRFU has steadfastly opposed Minister Ryan's proposals, claiming any move to designate the Six Nations and Heineken Cup as free-to-air would cost the organisation €10 million to €12 million a year.
Former RTÉ chairman Dr Farrel Corcoran, the current professor of communication at the Dublin City University, challenged that assertion today and said it was his strong suspicion some estimates were not accurate.
"I'm not an economist of sport," Dr Corcoran told the committee, "let others speak up on this. But I've a strong suspicion it is being exaggerated."
But the IRFU insist a very real threat exists to the security and financing of rugby at all levels and that the figures are correct.
"It is erroneous to suggest that the IRFU is overstating the financial threat to the game in Ireland if changes are made to the broadcasting legislation," the union said in a statement.
"The figures of between €10 million - €12 million are based on expert calculations centered on the contracts existing between the IRFU, the Six Nations and ERC.
"It is misleading for commentators to make statements suggesting that these figures are overstated and the IRFU believes that any such statements should be based on fact."
Dr Paul Rouse of University College Dublin told the committee that selling the rights to pay TV channels "doubles and even trebles" the proportion of the audience going to pubs to watch fixtures.
He said that not designating sporting events free-to-air for television made them less accessible for certain sections of society.
"In Ireland, sport shown exclusively on pay TV doubles and even trebles the proportion of the audience who go to licensed premises to watch matches," he said.
"More than that, the research shows that a significant proportion of parents who go to licensed premises to watch pay TV sports events also bring their children with them."