I think that portfolio's of software get messy in exactly the same way that joint research papers get messy: how do you figure out who did the work? That said,

I think that portfolio's of software get messy in exactly the same way that joint research papers get messy: how do you figure out who did the work? That said, I think you're right that in a large body of work you see the little eddies in the programmers mind, and thats an evaluative tool without comparison.