Gladiator, your attitude is slightly less than helpful to establishing the numerous factors which contributed to this tragedy.
It is universally accepted that SIA are not perfect. How far from perfect they are is a matter of debate and opinion.
But as long as people on either side are prepared to say "There - look there - it's HIS fault" and dismiss other factors because they put the "blame" elsewhere, there is little hope of learning from the accident and making changes to the entire system that will prevent a recurrence.
There is never a single cause of an accident. I assume you are familiar with the "Swiss Cheese" model? It is not enough to plug one hole. We need to plug all holes that are shown up by the investigation.