The focus on the airworthiness issue bothers me. It is obvious that there have been major failings in airworthiness for decades and, invariably, these failings are amplified during high profile BOIs. My concern is that the broadening airworthiness argument rightly casts doubt on findings but it does not necessarily provide cause. Personally I'm happy with 'doubt' but I wonder whether all those who were/are directly affected would be equally content. Whilst the airworthiness discussion continues we must continue to entertain rational arguments that attempt to identify the cause of this particular crash. Not having this discussion would be a disservice to our lost colleagues.