I'll be honest, I have no idea what the sentence means (long bow?)

But let me try to elaborate on my point. The author gives several examples and in each example he cites the person's job and then points out how the fact that they spend their time using the same skills in their personal life makes them the best qualified for their job. Examples

Greg Daniels: Job: Fishing Guide - Free Time: Spent Fishing Captain Sullenberg: Job: Pilot - Free Time: Accident Investigator for Airlines

So his premise is that people who spend their spare time using the same skills as they use in their jobs make better employees. He then brought up the Receptionist example and cited "throwing dinner parties" meaning the skill behind throwing parties is what he think applies to being a receptionist. But his thesis is the same he just sees the skill behind receptionist as socializing

My counter point to his argument was that diversity is valuable and that people who hone skills other than the ones directly related to their job are just as valuable because they can generate insights from those unrelated skills. That's why it's important to have those people along with the people who spend their free time on work related skills.