310: I'd strongly suggest you reconsider your notion of aetiology.
In the example you give, your argument is:
Tens of thousands aircraft land at the CGH, very few finished off the runway.
This one finished off the runway.
A major distinguishing factor is the TLA position.
Therefore, the TLA position is the "primary cause".
That's weak. PBL's counterargument is:
Numerous A320s have attempted landings with the TLA in the wrong position
This one is one of the few that finished off the runway
A major distinguishing factor is the shortness of the field
Therefore, CGH is the "primary cause".
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In history, we would call such an oversimplification an instance of the single-cause fallacy.
But the problem is, accident investigations are not pure historical endeavors. The investigators are charged with not only determine how an accident came about, but in making recommendations so it does not happen again. Their findings, and their recommendations carry considerable economic, legal and political weight. So, in arguing their point, they put forward a scheme of "primary" and "contributing" causal factors that don't seek purely to explain the event, but rather intend also to provide the foundation for their recommendations. "Primary/contributing factors" are the basis for arguments, not thorough explanations of the event. In other words, what's happening is that some of the causes - actions, inactions, conditions, circumstances - are being emphasized for purposes that are beyond simply explaining "what happened".
We had some bickering over the definition of the term "Accident", including folks citing Websters and lucky part 13 of the ICAO. But whatever the case is, I hope we can agree that most aviation accidents are the results of several factors: the "holes in the Swiss cheese", as y'all like to call them. A chance or fortuitous configuration of not necessarily related circumstances result in an accident. Well, every hole in the cheese is a causal factor.
Both the TLA remaining where it was and the short, wet runway are necessary conditions here. That makes them causes. Neither of them alone is sufficient to cause an accident.
Now, once you identify the causes, then you can go to the business of making recommendations, and cheerfully selecting whichever ones support your political, economic or safety agenda, and calling them "primary" and "contributing" causes. But, in themselves, and in the event, "primary" and "contributing" causes have no meaning. There are just causes, and sometimes effects.