"Flip-Flopping" and Honest About-Faces by Law Professors

At the Faculty Lounge, Brendan Maher asks an interesting question about "flip-flopping" law professors: 

I periodically wonder how frequently legal academics sincerely change their minds about things they've written previously.  Changing one's mind on the truth of a previous proposition asserted is a different matter than admitting the change; the latter's less frequent than the former, no doubt.  Just the same: what's the most famous about-face in legal academic history?

"Flip-flopping" obviously has a negative connotation, and sometimes it is a sign that a law professor has adopted inconsistent positions for the sake of achieiving some political goal.  (I have no one in particular in mind here, but, by way of example, in recent years a number of people seem to have argued both sides of Boy Scouts of America v. Dale depending on the issue involved.)  Sometimes, however, a scholar reaches a genuine conclusion that his or her prior view just doesn't work or has more problems than he or she initially accounted for, and the public volte-face that results is often not only useful but heartening, as a sign that some scholars take their vocation profoundly seriously.  In my own field of law and religion, I think of Chip Lupu's move from being critical of church autonomy to arguing in favor of it.  Lest I seem as if only those moves that I favor are praiseworthy, I also think of Fred Gedicks' move from a full-throated support of group rights to his more recent work calling a group rights model of constitutional law, and especially law and religion, into question.  

A somewhat different example, but one that has always fascinated me, is the story of Henry Hart and the Holmes Lectures.  As Bill Eskridge tells it in his Harvard Law Review article on the making of The Legal Process: "Hart's 1963 Holmes lectures illustrate the intellectual paralysis engendered by his perfectionism. He presented a detailed argument in the first two lectures. During the third and final lecture, Hart announced that his proposed resolution did not work and sat down before a stunned audience. Although the terms of the Holmes Lectures required a manuscript to be delivered for publication, Hart never worked out the problems with his argument and never delivered a manuscript."  (The story has been well-told in many places; Laura Kalman's telling in her book The Strange Career of Legal Liberalism is a particularly good one.)  

Brendan has asked a good question, and one that in different ways may help us to reflect on what our vocation requires.  I take it everyone agrees that scholarly flip-flopping or inconsistency for the sake of politics is a failure of scholarly obligation--and, conversely, that it is worthy of praise, and perhaps even obligatory, for scholars to publicly declare it when they change their views.  I hope folks will weigh in, there or here, with other examples, either of less praiseworthy "flip-flopping" or of commendable public changes in position.