The swiss cheese model is a very good one, and not at all trite. You are quite correct though in that it doesn't differentiate between the relative elements, because removing any one of the elements might presumably remove an opening for the accident occurrence.
A debate on the relevance of the "Swiss Cheese" model is probably outside the scope of this thread. Let's just say I disagree, and it predisposes to "hindsight bias" - which involves placing undue significance on factors that prior to the event should not have been relevant (like the high altitude NAV track being different to what the crew expected).
What might have been the outcome if the "Ops Flash" at the top of the flight plan had the message "McMurdo co-ordinates changed"? Would the crew have said to themselves, "I wonder where the new McMurdo is?", and then gone to the trouble of plotting the position?
Maybe. Maybe not. But provided they stayed above MSA, the worst case scenario should have been what happened on Capt. Simpson's flight.
But I forgot, the airline invented aviation.
They certainly didn't set up a bullet proof infrastructure, that's for sure. But in this whole episode - if any parties can be accused of making up the rules of aviation to suit them; it would be Collins and Mahon.