I agree witht the simulation theory,
next time you have 5 minutes to spare on the ground, leave the machine running and start simulating failures, pulling breakers.
If there's FD bars on the AH, there's also warning flags, so just pull breakers untill they pop up.
Try different scenarios as well, 1 gen versus the other, emerg bus on or off etc., I'm sure this way you will figure it out + it will give you a better understanding how your machine is wired.
By the way do you need any extra pilots out there?