Roberts has much higher standards for “abandoning any pretense of jurisprudence” than his party does. He’s opposed to doing so when it’s too obvious. For instance, he had to vote the way he did re: the Louisiana law because there was no legally credible way to support it given than an essentially identical bill was tossed just a few years earlier. Shelby County, OTOH, was tossed by making an argument that the VRA did the job so no need for it anymore. (Not that the argument was correct, just that one could be made without sounding like a nut job.)