When I presented a draft of Rehabilitating Lochner at the NYU Legal History Colloquium a while back, several participants took me to task for "wasting time" in spending several paragraphs rebutting the notion that Lochner and other liberty of contract cases had their origins in "Social Darwinism." The critics correctly noted that revisionist scholarship over the last forty-plus years has eviscerated this myth, but were incorrect in adding that "no one believes that anymore."
Thanks to Google Books, I was able to do a search for Lochner and Social Darwinism, and found the claim that Lochner was a product of Social Darwisnim recently repeated in the The Oxford Guide to the United States Supreme Court, in a book by prominent political scientist Rogers Smith, in a book by William Rehnquist(!), among many other sources.
This raises the interesting question of how long it takes before a consensus view of "experts" in a historical subject drives out longstanding contrary myths that non-experts continue to propagate.