From the responses generated by the first threads that Ian started and the first nine posts here, there is no doubt that the first area of enquiry is
not the carriers but the regulatory bodies. If they choose not to see transgressions - then the carrier can do anything they like.
Secondly, I suspect from Ian's brief:
... investigating safety standards within the airline industry in general, and within the low-cost operators in particular.
and by his line of questions, that LoCos are in the firing line. I do hope that does not obscure what the legacy carriers are doing. They know what they are doing as they have been playing the game for a long time! My reckoning is that Pax assume that LoCos are cutting corners and the Legacy carriers are not. All that I have seen on PPRuNe in the six years I have been fortunate to read the forums - says that is not the case.