1. Become the best at one specific thing. 2. Become very good (top 25%) at two or more things."
I'm certain at least some small part of my own success can be attributed to my exposure to this idea, and for that I give my respects to Adams. As far as Adam's character (or lack thereof) is concerned, that's already being discussed elsewhere in this thread by others more eloquent than myself, so I'll leave that to them.
Is this idea that top 25% is "very good" at something innumeracy, or a subtle insight I'm missing? There's got to be a million skills that you could assess rank at -- writing embedded C code, playing basketball, identifying flora, PacMan, archery, bouldering… I can't imagine ever being able to not continue this list -- and you should expect to be in the top 25% of roughly a quarter of those skills, obviously heavily biased towards the ones you've tried, and even more biased towards the ones you care about. It's hard to imagine anyone who's not in the top 25% of skill assessment in a dozen things, let alone two or more…