@ BigDog. – 30/05/2013 14:43 GMT
As you say, basic probability theory. Or, to paraphrase the redoubtable Lady Bracknell in “The Importance of Being Ernest”
“To lose one may be regarded as a misfortune; to lose both looks like carelessness.”
I should imagine that BA’s Head of LHR line maintenance is currently having a few sleepless nights at the prospect of the AAIB investigation potentially revealing serious and serial maintenance shortcomings and lapses.