Herringbone is an elegant name for a very simple pattern. I don't think it requires enormous brains to repeat a zig-zag.I've obviously never laid pavers on a street, but I imagine it really could be, especially for a project like this. Remember that the pavers were designed to be laid out in several different herringbone patterns (to resist ware), and that Nicollet Mall has curves. At every boundary, at all intersections, and at the curb (both for the sidewalk and the road, since the pavers were for both) you have to fill in the correct space with pavers that have been cut to fit. So you would need many thousands of small, precise cuts on pavers that you can't really afford to make mistakes with. Sounds like a lot of work to me.Second, the idea that labor costs make installing a certain material prohibitive seems a bit silly. It's expensive to have workers pour concrete. Is it so vastly different to lay pavers? Probably to a degree, but not in kind.
Of course it requires some skill. But construction requires skilled trades. Why should this be any different? How does this one material entirely change the equation?