Judd, villas, well said and I think on-topic insofar as we are digging around in human performance aspects of aviation accidents, which AF447 is, (again emphasizing that blame is not a part of this kind of examination). In this there are perhaps some commonalities between this and the Colgan accident at Buffalo, (I know this has been broached previously...just making the connection on "Thread 12").
A technical question regarding the Airbus which may have been answered in the other threads - IIRC there was mention that the stall warning could or should inhibit movement of the THS - I believe there was something in the Perpignan accident report about this. There is lots to think about in such a design - should it do so in Normal Law as well as the two Alternate Laws? However, were it to do so, would it limit elevator authority if it did not move in response to elevator demand as ordered by the stick? Would there be a need in "normal" flight for a THS setting of -13°? ...in Alternate Law?
It is hard to think of such a case at cruise altitudes, but what other considerations might there be that makes it a better idea to place limits on THS movement in certain phases of flight?
These questions will have been thoroughly thought through of course even if some might consider the design puzzling in the hindsight of the accident.