I have 3 glocks, a smith J frame, a 1911, and a full size S&W 45. I have to say the S&W full size 45 is the safest. If you carry it with the safety on, the trigger is disconnected and it is impossible to discharge. Once to take it off then the double action first shot and grip safety is pretty darn safe. With that said, yes the glock makes me a bit nervous with no safety and a light trigger. Carrying the glock in a good holster is the best safety second to operator control.
Many of the discharges discussed probably occurred in the years when LEO's transitioned from revolvers to autos with the light triggers, due to pulling the trigger under stress. Many police departments went to the Glock NY-1 trigger with 8 lbs pull instead of the stock 5 lbs. This trigger allowed for a firm consistent pull similar to a revolver. Massad Ayoob on page 27 in his well know book Combat Handgunning talks about how he has modified all his glocks with the NY-1 trigger. This $2 modification is a great option for folks that want a safer more revolver like gun.
Yes there also the stories about how LEO's lives were saved because a bad guy tried to kill a cop with their own gun and didn't turn the safety off, but I am also sure there are stories of cops being killed because they forgot to take the safety off their gun, who knows.
Personally, I fell a cocked and locked single action gun like the 1911 is as dangerous a weapon as any out there, and would take the revolver or Glock any day as far as piece of mind carrying goes.