Is Unique Knowledge Better Than Specific Knowledge?

I came up with this framework when I was really young and we're talking decades and decades. It's now probably over 30 years old. At the time, just specific knowledge stuck with me so that is how I think about it. Scott Adams' blog post on how to build your career by getting in say the top 25 percentile at three or more things. By doing that, you become the only person in the world who can do those three things in the 25th percentile. So instead of trying to be the best at one thing, you just try to be very, very good at three ormore things.