[MilkMaid]

I think people are not so dogged in 'real life' to 'pull people up' on things.

If I were having a conversation with someone I might notice them contradict themselves but would consider it impolite to point it out, unless I were trying to be argumentative or felt sufficiently insecure that I had to be seen to be right all the time. Hence I think Dan's approach does underline his past.