When roll backs occur, it is not good for the computer system. Unless a ride op has figured out a loophole in the system, they can't cause a rollback on purpose unless they somehow close the brakes through the launch area while the train is traveling through it. But 99.9% of the time, it is random.
On Flight of Fear there is a glitch and you can about the launch but other then that they do not have any access to close brakes when they please. Only to release them when a train is in the position. Example would be to bring a stopped train into the station. The control panels are very easy to operate and is foolprof in a sense.
Yes you can abort the launch on FOF. But ride ops can also stop the train in the brakes by E-stopping the ride if they need to, which is what I was referring to in my origional post. I am very familiar with the control panels and know how these rides operate.