You probably just had a better opportunity than most to meet lots of people, increasing the likelihood of running into someone kickass and becoming friends with them.

Growing up in a university town it's true that I had a lot of my friends move away because their parents were students or faculty getting transferred- MP, BS, AS, KM, BN, and many of the friends that I did keep ended up getting shifted like my friend SN to another class group in the following registration period (although actually it was my parents transferring me to whichever teacher had the strictest reputation, I found out later).

Still the turnover was not sufficient to explain how then (or now in the following years) such a property has been conserved, lest I in my brilliance unwittingly just cause people to be born at certain times or they were all drawn to Iowa by delicious soybeans. The position of Ames as "one of the best-ranked cities of its size" with "a nationally-recognized school system" is pitiful. Each of those superlatives are based upon awful metrics, yet no one I've met belongs as one of the five trapped forever in Gehenna to my knowledge, unless they now author unthinkable chaos behind closed doors (CS may be a mass-murderer, but she really has no concept of what she is doing so that doesn't count...).