In the case of XV179 Inquest, the MoD will have had months to look through the evidence ahead of the actual date of the Inquest. Requests for legal funding for the families have been turned down by the very same MoD indulging in taxpayers coffers for their own defence. The failure of USAF to cooperate will not be a problem for the MoD. Remember they lied about the presence of the HUD video in the Matty Hull Inquest.
Cast your mind back to the Lynx shooting down in Basra. National security was the reason given for the highly redacted BoI. I happen to know there is another reason, similar to that described by AA. I contacted Andrew Walker's Office with regard to the Lynx, he had the information but it remains classified.
The XV179 BoI does not mention SF. If we are down to this level of censorship I am not at all sure we will get the level of openness that this case desperately needs.