Dozy,
You say that, contrary to my post, "BZ would not have been responsible for implementation details such as whether to interconnect controls or not - that would have fallen to the aeronautical and pilot engineering teams to hash out."
To indulge in thread drift: whom do you have in mind?
Around 1986, when we were discussing the feature in study groups, we were told informally that it had been insisted on by BZ. After all, he was the senior vice-president for engineering around that time, and we understood he was in charge of the FBW project. He was himself an experienced test pilot, and former chief test pilot of Airbus.
Gordon Corps joined AI in 1982 as an engineering test pilot, with special responsibility for flying qualities. No doubt he would have expressed an opinion on all these matters, but presumably his remit would have extended only as far as advising the handling properties, and the requirements for type certification. Subject to that, major decisions on systems design would rest with the engineers, IMHO.