Saddened to hear Blacksheep's account of the Vulcan trainer fatality; I always regarded the Victor Crew Drill Trainer (CDT) as the thing that would gradually boost confidence the more you used it (No 1 PTS motto "Knowledge Dispels Fear"?, which could equally apply to the rotary dunlker).
Personally, I thought that the CDT was a positive experience, but I must confess that one of my AEO's was convinced that no rear-crew would survive a Victor abandonment, and so, in my opinion, he doomed himself when others may have survived.
Concur Mike Jenvey's comments about the physics of the seat, the cushion just got one's CofG forward of ones toes, it was all down to gravity thereafter.