There was a time, when for 3-4 flights over a couple of years, I would always meet someone I knew, so much so that my pre-teen son (in those days) mentioned it. Does not happen any more though, my streak just ran out :)
But I think if I use your approach, I may always find someone traveling who knows someone that I know.
Reminds me of my grandparents while they were alive. No matter where we went with them (often on family vacations all over the US and Canada) they would find someone that they either knew or someone with whom they shared a mutual acquaintance.
But I think if I use your approach, I may always find someone traveling who knows someone that I know.