I once found both axles twisted round a spline and a half... but not broken.... if they break the will quite often make a mess of the centre (LSD or locker). I have broken axles in lockers, but the most twisted ones came from my tight LSD in the road car. At that stage I was not marking axles left and right when I removed them. Swapping side to side will undo the twist, but it will almost certainly undo all the way (off)... Axles get the hardest time on initial takeoff and during gear changes as well as transitions from surface changes (ie dirt to asphalt)... When already going sideways with both wheels spinning unless you hit something(changing the relative grip or shock loading) the axles are getting an easier time than a hard takeoff or hard gear change. Axles I have broken are:
-2 in gearchanges
-1 from backing off over rough corrugations
-2 from reapplying power after handbrake turns...
All on unsealed and all with lockers... never broken one on the road or in an LSD or since marking them left and right.... broken axles can be made into great exle pullers.....