Whoa there, hoss.
The ADs suggest that the FDs should have extra logic to force and latch them off in the case of UAS, but it's a stretch to say that this is what happened to AF447. More likely they identified it as an issue while running the sim checks and want to close that particular potential hole in the cheese.
I still don't buy the idea of a pilot following FD in the middle of (what started as) a minor emergency situation such as this unless they have a serious scan breakdown - as I said earlier, the FD is for navigation - not aviation. The other reason is that the FD would have been taking it's information from the selected values, correct? According to the trace, none of the "Selected V/S" values during HN39's excerpt even come close to requiring a 15 degree NU climb.