You seem to have missed the part where the extreme example is not real life Actually, I referred to your example as both 'extreme' and 'artificial' in my previo

You seem to have missed the part where the extreme example is not real life Actually, I referred to your example as both 'extreme' and 'artificial' in my previous post. Since the example was constructed to make your point as obvious as possible I was just pointing out that in fact P(B|A) was actually useful even in that example. Sorry for the delay in responding, I gave up yesterday because there was no option to reply even after a very long time.