Hi,
Roll over is never a good thing but operators should be trained for such an eventuality.
Trainers must emphasize strongly to the operator the responsibility involved in handling a HIGH RISK machine. Here in Queensland the government has stated that operators will incur heavy fines if they don't carry out their duties as they were trained. The problem with that is (in my opinion) there are not enough inspectors checking out workplaces.
UNTIL of course an accident happens and then all **** breaks loose.

Pat