i'm still not totally convinced of the suicide angle. Without knowing precisely how long that cockpit door would hold, a suicidal FO in total control of the aircraft would dial in a 3000fpm descent from FL380 and then sit back and do nothing? I know suicidal people are irrational by definition, but with full control of the situation, for an unknown amount of time, one would think a much steeper descent, and a turn to the closest terrain linearly would have been in order? Seems more likely that the FO was not conscious for whatever reason sometime after the Captain left the cockpit.