. . .would have done, but if it's axis Z, so be it
.
I am not so sure the elaborate armor of the JLC is necessarily going to help. There's a big difference between damping the effects of a sudden deceleration, and tolerating sustained high G loads. I suppose you could even pull the hands off their pivots
except what might save them is that their mass is awfully low. One possible outcome I guess is that the balance pivots will be under such high pressure that the balance will simply stop.
I guess it's possible that the vibrations will work parts loose as well- although we might perhaps all be surprised at how well the watches tolerate the test; everything's held in place with screws after all and for something to tear loose the screws would have to have their threads sheared off. . .
I dunno. I guess we'll just have to wait and see 
Jack