Pontious, I'll take your word for it! However, in the RAF we used to say the same thing. Inevitably, there were times when so many made, or could make, the arbitrary 'standard' that, in the short term, the interviewers were 'guided' towards a tougher line, and in the longer term the standard was raised - the training system could not cope with unlimited numbers of students, and the RAF knew very well how many new peeps it needed every year. And, when applications were a bit thin, vice versa. The net result was that only a certain percentage would pass, which is the way they wanted it. For the candidates, it always effectively meant that only the very best of those who attended would succeed. In other words, they were in competition, whatever the official line was. If BA has managed to avoid the peaks and troughs, and can genuinely say that all who make the (unchanging?) standard will fly for them, well done! Forgive me for being just a little bit cynical about that.
Whatever, I stick with my final sentence of advice - go in to this planning to be the best candidate they inteview, not just good enough.