In procurement in the late 90s/early 00s Defence was not allowed to buy stuff that provided "interoperability" (fortunately common sense has now prevailed and interoperability needs to be considered).
Spot on Roland. (I'd say most of 90s to at least mid-00s. A major Cat A Army programme was still rejecting interoperability in 2007). If you study successful programmes in those years the common denominator is we completely ignored such edicts, as far as possible. It was such a gob-smackingly deranged policy that few today would believe it, so I'm glad you mentioned it.