two people with high IQ will out-perform a single person of super high-IQ
Out-perform them in what? One of the biggest issues in programming is a group of programmers is only as smart as the least smart of the group, unless the rest of them just ignore the lesser. I've had it where about 5 of the most senior programmers in my company where stuck a problem for several days with code that they wrong. I just so happened to have walked by and overheard them discussing the issue and I solved the problem in less than a minute. It was a 100% custom built system, so I had zero knowledge or experience. This pretty much sums up every experience I've ever had.
Another example. My ISP was having a network issue. I was working with one of their senior engineers for nearly 6 months. I kept telling them what the problem was and where they need to look, but they couldn't figure it out. They eventually hired a 3rd-party firm that specialized in fixing complex network issues for large ISPs. Even they could not figure it out for several days. My ISP called me and asked me to talk to these people. I got on the phone with 3 "specialists", and I went over the data I sent them, explaining what I thought the issue was and the reasoning behind my thoughts. I got off the phone, 1 hour later, the problem was figured out.
My background in networking is I took an entry level class in college and I have a pfSense box at home, and I diagnosed an ISP level network issue with nearly zero experience.