Foxy, I think you're being a little paranoid.
I hope so!
Personally, I don't think Duty of Care
needs defining. Surely any one of us would exercise it anyway? I take it as read that it is an important aspect of the job, part and parcel of holding a licence.
ISTR - sorry, that's an abbreviation I don't know

I think I catch your drift though. It just so happens that many (and there are many!) of my ATCO friends think the same as me. None of us remember this being in consultation at all, TBH, but the Duty of Care bit is not something any of us feel particularly comfortable with.
NOT because we are routinely negligent I add (quite the opposite), but because we fear that that any one of us could find ourselves, through no fault of our own, in a situation where, if an incident
did result in serious injury or death, Clever Lawyer could make a case against us aven if we weren't really at fault. Putting it in writing can be interpreted as a bit of extra ammunition.
However, that said, it's certainly something that'll keep me knife-edge sharp from now on! I'm glad I'm being paranoid....
Time for me cornflakes. Sorry if I've rambled a bit - lates last night, and woken up too early by the 'kin rain!