92125 (PS are you a railway enthusiast?)
The accident rate affected by 'certification' is that relating to structural or control system failures. I maintain that this rate has not reduced (it was never high) since my time.
The biggies were always winching accidents and cross country flying. The winching accidents have been reduced somewhat due to the very active intervention of the BGA. How did the ATC handle these accidents?
In thirty odd years of gliding I never saw an accident which could be attributed to structural failure. Plenty messed up winch launches though.
I have still got my 'B' badge. The first awarded in the Staffordshire Gliding Club.