The DFDR is a wonderful tool, as is the CVR. It is tempting to enjoy the luxury it affords us in hindsight. It played no role in the disaster. NONE. To the extent that anyone believes it will cement a complete knowledge of the cockpit events it is useless (but will help a partial picture). It also is useless and worse, if people misunderstand the exact events, the cheeses, and allow it to cloud an objective view.
We see how important is the language of the events, and the "reporting" of the language. To this day, there are those who have a reaction to "En ligne de Vol", and reject its nuance, in favor of bastardizing its meaning to cement a foregone conclusion.
The Human accelerometer is in the butt cheeks, and the computer in the Inner Ear. How ironic and frustrating that had the pilots been instantly privy to a readout of the guts of the boxes, this thing would not have happened. I think PF was trying doggedly to incorporate his human sensing skills into his flight Path. "I feel some crazy Speed....". Vitesse feu. Don't go there cowboy.
In that, there be demons.
BUSS takes us in the direction of the "Problem solving by computer", when the human is not equipped to figure things out, either due to lack of capacity, or shortness of time. OR the inability of the Flight computer to find the words, and the pathway, to tell him/her. Quickly.