AirTren
Certainly I accept your explanation and am sorry if I imputed too much to the changes.
My point is not about the type of people, qualifications or standards they have to meet. My point is about how people comprehend signals via various stimulae. It varies and we cannot be too dogmatic or assume that everyone will respond in the same way to the same stimulus. We cannot even assume that someone will respond the same way to an identical stimulus all the time. This affects all sectors of society and all professions. Aviation history is replete with accidents caused by pilots missing visual and/or aural cues. Even an otherwise excellent pilot may miss a cue on that one vital occasion and precipitate an accident. This however is drifting off the subject somewhat.
Perception, interpretation and comprehension play a far more important part than the nature of the visual or aural stimulus. If you set up a frame of reference you enhance the chances of a correct understanding of the situation. Sometimes direct is not the best.
Last edited by Old Carthusian; 15th Nov 2011 at 09:46.