Originally Posted by More Champagne Sir?
100% Strict. One means One. No exceptions.
Unfortunately

Not 100% correct if my experience serves me right
I managed to get a carrier bag containing duty free, in addition to my hand luggage through T1 Domestic security this week.
I almost cacked in my pants when I remembered the restrictions (was landside when the penny dropped) and was prepared to dump my hand baggage if need be. Luck must have been on my side.
I expect this was one of those rare exceptions