Even if you were to accept this point, you would need to be sure that the authority responsible for calculating the expenses and spending the money is competent so to do
That's always the case. To be fair, up to recent years, the policy environment aimed to obstruct the development of Dublin Airport. It can be hard to disentangle what is down to the management, and what is down to that policy environment.
I suspect the future will be quite different. But I do agree, DAA will have to demonstrate delivery.