I am not entirely sure, but I believe in this case, the different people/personalities have very distinct and obvious behavioural differences. I believe what Binky was trying to say was that he had not experienced these obvious behavioral differences and therefore his only experience of her multiplicity was 'her talking about it all the time'.
He was sceptical, but had no objection to her leading her own life, or ahving her own choices apart from when they interacted negatively with him
He has at least been polite, and not insulting, as well as shown an interest in learning more.

For the record, I've withheld judgement. I simply do not know enough about multiplicity, DID/MPD or Chris to make any kind of judgement.
I'm still hanging around here because I find the conversation interesting.

I do find it a little hard to swallow that the same people here who are so vociferous about people being understanding about other people are the same ones bagging my entire social group based on very little indeed. But hey, thems the breaks.