In their final response to the commission, lawyers for the media firms said differences between those who are for and against the merger was "a contest betwen hard data on the one hand, and wishful thinking on the other".
The lawyers said the parties had submitted extensive data about share of the advertising market, market trends in revenue, synergies, and efficiencies, and accounting expert reports on the logical and necessary conclusions from the data.
"In contrast, a large number of submitters in opposition have presented the commission with their views as to why the businesses have not been successful (although they have not run those businesses in the recent - accelerating - market conditions).
"They have also expressed hope that different combinations of businesses in [the] market might present a better alternative to the proposed merger."
But the lawyers said the proposed merger had not been put to the commission lightly or too early.
"The necessary corollary of that is that it cannot be put to the commission later, because later will be too late."