Grandstanding Representatives and Senators at a Congressional hearing doesn't mean that Congress has any approval/disapproval say whether or not two companies merge.I think there was a congressional hearing,from what i can remember, and Parker was chastized for coming up with the 11 billion $$ for DL, when only a year previous, U had dumped all the pension plans to the PBGC before emerging from BK again in 2005.
A lot of people see their Rep or Senator grilling business people at a hearing and assume that the Congressional hearing is part of the merger process, when in fact it is not. Just grandstanding politicians.
Creditors always have the final say in bankruptcy - after all, they get a plan of reorganization or the debtor is liquidted, and they vote on which they will accept. Parker's attempted hostile takeover did not fail because of any antitrust concerns - it failed because the DL unsecured creditors didn't vote for Parker's POR.From what you post, the creditors had the final say, but I believe there were antitrust issues at that time with regard to legacy carriers consolidating. Consequentely, the consolidation occurred with the laegacies anyway as time progressed.