As I stated above, if you collide with something while you are moving and the object you hit is stationary it is pretty much your fault. The root cause is always that you failed to see and avoid. You should try and not depend on others to always do what is expected to the extent that is humanly possible. Do not confuse what I'm saying with the fact that any or all of us might have had the same outcome causing those of us watching to say " yeah, that could have happened to anyone because they were set up by factors beyond their control". Yes, the scenario was beyond expectations of the pilot but that is why we drill and drill and pay big bucks for SMS programs that all have the same risk assessment matrix in them. If they had such a program and did an internal audit on ramp procedures perhaps the poor selection of how they parked aircraft would have popped and things might have been different. Laugh if you like about the chance that that would actually take place but if we follow our own advice and actually do these things, it might surprise those who are sceptics that it can work. That doesn't change the cause of this accident. The root cause doesn't necessarily go back to the one, two or ten things that might have prevented the accident. The root cause is that thing that actually allowed the rotors to hit. This factor was totally under the pilot's authority to prevent and that was the controlled flight of the aircraft in motion. You might argue the analogy but when you run over your kid's bicycle because they laid it down behind your car in the driveway, it is time to yell at the kid for being dumb. However, in those tragic accidents when it it a toddler that is injured or killed because someone didn't see them...is there really any blame placed on the child?