You implicitly assume such a measure is theoretically possible. Perhaps it is, but just asserting this as fact is not enough to make your argument valid. I bel

You implicitly assume such a measure is theoretically possible. Perhaps it is, but just asserting this as fact is not enough to make your argument valid. I believe that product development is creative, collaborative work and that there is no theoretical or practical way to design any sort of universal scale to rate individual contributions into it. Each team and problem combination is different. If I'm right with my belief your argument falls down. Not only that, but if I am right then what comes into play is team and collaboration dynamics, which rely on trust and safety far more than on individual brilliance. If so, any attempt to "get rid of the bottom half" will simply destroy collaboration and guarantee a dysfunctional product team.