Your JTIDS comments reminded me that it was the same MoD Directorate/IPT that implemented the above polices so zealously, their mantra being "It works on the bench in isolation, so there is no need to integrate or test it in the aircraft". Hence, Burridge's recommendations regarding functional safety of the IFF in the ZG710 BoI.
Slightly off topic but definitely true on one job I supported in about 1999. JTIDS was bought from the US but integration was ignored by the department you mentioned and had to be contracted to the UK's JTIDS experts. IIRC they also said the sims needn't be modified and no tech pubs or spares either.