Nervous mechanism, maybe? My STBX 'N' would also almost always say to anyone we met 'Do I know you? You look familiar.' But given her line of work where she met tons of people all the time, I just chalked it up to that.

Sounds a bit like my Ex gf. She somehow knew all the French TV personalities be cause they lived near our geographical location of residence or in her region where she was born. Seemmed ludicrous that she knew all those French TV personalities. And she was into the professional athletes of major sports teams here and so forth. In short , into everybody but me. At least that was than. But she knew them. She was not uncertain as to whether she knew them or not. And she was not into Cannibas or the like .

My exN perpetually did the same thing too, and is also a substance abuser.
I came to the conclusion that there were two things happening. That he used this technique to try and draw the people he met into some type of false intimacy, and he was especially competitive with the people I knew. And I also think that because of his substance abuse and wild times out meeting heaps of people, he would mention that he may 'know them' because maybe he had in fact met them and hadn't remembered.
But I mainly think he used this strategy to form intimacy, and this kind of charmed the people that were maybe less strong around there boundaries, and annoyed the people who were strong.
My good friends mentioned this to me early in the relationship as something they found strange and kind of invasive. He did the same thing to me when we first met, and I was stupidly charmed.

I agree with samesame68, I think it sounds like something that would help him bond quickly with others, maybe even open a conversation about where they might have met?

I understand what you mean about weirdness, my N was so weird in the end I kinda took it as that was normal but it's when you're out of the relationship that's when these things all come back. constant wtf moments!

My hunch is that like Douglasn, I found it ludicrous and impossible. Some delusion of grandiosity, that he knew the whole world.
That and the spliff had mashed his brain.
But I totally agree with samesame68 & strengthinadversity that it felt strange and invasive, like a boundary invasion.
If you have weak boundaries, you may think "how do I know you", and start wondering! It must be a creation of false intimacy, that would have gone unnoticed had it not been so repetitive. I too stupidly fell for the charm & intensity - I have never been with someone so intense. And, as it turns out, so meaningless and empty.

Love to all - love this site
Peace, Love

PL xxx

yes strengthinadversity - constant WTF moments !!! that ol' gut instinct !!! xxx

I think Samesame's comment is quite insightful ... it would tend to draw the (new) person out as they and N might then engage in conversation to discover the (supposed) connection ... very expertly giving the N loads of information that might prove useful then ... or down the road.

The one I was with never said that, but was VERY friendly, even to the point of being somewhat annoying. Try that with someone and pretty soon they are feeling like you are an old buddy. I watched him do that with my friends, people I met in nursing school and so on, that he would not have been friends with otherwise. I got to the point, too, of having panic attacks when I was staying with "my" friend after leaving the first time he filed for divorce. I later realized it was because he infiltrated himself into all my relationships and I wasn't sure I could trust anyone, because he was seen as such a "nice" guy by one and all.