would you also not want to look at what stupid flying time airlines now show on websites, timeables etc so that even a very late departure from one station can still show as on time or early, for example the flying time from London to Dublin has been shown as getting longer in recent years yet i would suggets that for example lhr-dub is in reality 45-50 mins rather than the one hour to one hour twenty that some carrier show, therefore building in a time that massages the facts.