However it also states that, 1) the stats provided by the airport demonstrate poor performance and 2) that the airport accepted that their performance has been unacceptable.
You can dismiss it as 'crap', but the fact is that this is yet another piece of evidence which correlates with an ongoing pattern of poor service and increasing customer dissatisfaction.
I actually provides almost no stats. The Executive summary contains information that is not present in the main body of the report, let alone expanded upon. Yes, the airports all have admitted to issues, but given the CAA has an enforcement role, there is an incentive to do so. In the case of Manchester, there is/was a clear issue with understaffing and as a result wait times compared to the 'targets' set by the CAA. We aren't told what those targets are or what the basis for them is, so it is effectively impossible to determine if they were actually 'correct' in the first place. That said, you are correct that there a significant signs of issues with poor performance in a number of areas at MAN, but the data presented is so poorly done that you cannot definitely say they exist. As for increasing customer dissatisfaction, at least in the CAA report there is no evidence of such, just evidence that the airport remains at 'Poor' on their criteria list. Keep in mind according to Appendix B and airport could rate poor and actually have very low dissatisfaction percentages.