Peer review isn't measuring in this context. And often the value is hard to understand. I thought one guy on my team was clearly weaker than the rest... until I

Peer review isn't measuring in this context. And often the value is hard to understand. I thought one guy on my team was clearly weaker than the rest... until I realized what he did that no one else did, which turns out freed up the rest of the team to do stuff we were great at. "Better" isn't linear. It can multiply, and it can be highly dependent on the rest of the team.