I think I am missing something...whats the statistics thing now?
The party composition is exceedingly unlikely to occur as a result of the random sampling the mindflayers are shown to practice in the intro. Characters who appear to be somewhat normal are somewhat normal in most cases while those who appear to be very strange and are known to hide big secrets tend to be untrustworthy.
I sometimes use thought experiments. I don't necessarily believe in every idea I post for discussion on this forum