What you ladies need to remember is our number of OK's does not always equal the number of providers we've actually seen. Sometimes we might see women that are not even on P411. Sometimes we don't even ask for an OK from everyone we meet. Some ladies will give you an OK without you even asking, and I know some guys only keep the OK's that they specifically asked for. Sometimes we simply delete OK's for various reasons.
Some of these guys could be considered serial hobbyists by your definition, but you would never know from their number of OK's or when you met them in person. You can't always assume because he only has X number of OK's, then he must not be a serial hobbyist.