Re: Just refuse to discuss it
I think he was so calm because he was recording it and knew what was going to do with this.
I've thought about doing this in the past with some call centres, but I read somewhere that it's illegal (in the UK anyway) to record a call without the other person knowing. Chances of being prosecuted in cases like this is very slim though.
I'm surprised that more people don't record calls like this - they're far too common.