For what it's worth, 3 of our 8 775s had a short to case. I had marked them as "bad" and was going to pitch them in the trash. After reading here about the zaping procedure I figured what the heck and gave it a try. The zaping procedure seemed to fix all three of our motors, however, we will still not be using them in competition and are considering not using any 775s at all and changing our plan to use 550s and the FP. I am pretty disappointed in BaneBots over the years and this just adds insult to injury.
Of the 3:
The first 2 sparked somewhat spectacularly both apparently from the larger holes near the back/terminal end.
The last 1 produced almost no spark at all and was only visable as a tiny (~1/16") arc when the wire touched the case. No sparks apparent coming from inside the motor.
The first one we zapped with the lights on and sparks were clearly visable even in a well lit area. For "effect" we cut the lights off on the last 2 and the first one sparked nicely and the last one was the one with almost no spark which probably wouldn't have even been visable if the lights were on. On all three it only took one zap to fix the motor. The procedure was about as simple as it gets. I took a robot battery plugged in an Anderson connector with bare wires, held the red to the red terminal on the motor and touched the black to the case. No breaker involved. For as strange of a "recomended fix" as this is it seemed to work. The second motor we did does have a slight burned black line on the case where the wire touched. Other than that no other obvious signs on the outside other than where I wrote on them with a Sharpie.