There are parallel arguments, but also differences between these authors. To guide readers, I asked Grossman to compare and contrast their works. He accomplishes this principally by laying their arguments about similar issues side-by-side. I invite Tamanaha (and others!) to weigh in. It's best to begin with the papers, noted here and here. Grossman's comparison follows:
The Realist Characteristics of the “Formalist Age”
Tamanaha p. 5: “Judges, lawyers and theorists did not widely think of judging as a mechanical or deductive process. The legal realists were not pioneers of realism about judging. Just about everything the realists said about judging was said decades earlier by individuals who have been identified as important formalist thinkers, as well as by many others in legal circles, including a number of accomplished judges. The US legal culture has swallowed whole a largely fictional tale about views of judging during the so-called ‘formalist age.’”
Grosssman p. 217: “The debates over codification described in this Article demonstrate that jurisprudential strands identified almost exclusively with twentieth-century legal realism were substantially present, if not necessarily dominant, during the late nineteenth century. I thus challenge the long-dominant mode of periodizing the history of American legal thought.”
Antiformalist Views of Late 19th-Century Practitioners
Tamanaha p. 35-38 (from section titled “The View From Practice on Law as Science, and Judging as Deductive Logic”): “[T]he ‘law is a science’ phrase . . . was regularly invoked in the latter part of the nineteenth century, particularly by jurisprudence scholars. Throughout the formalist period, however, legal practitioners were openly skeptical. . . . An academic advocate of seeing law as science acknowledged (in 1895) the gaping divide on this issue . . . . The same gap in views [between academics and practitioners] is evident in connection with the notion that judging is a matter of mechanical or deductive logic.”
Grossman p. 197 (from section titled “Practitioners Jurisprudence”) : “The struggle against codification thus inspired an extraordinary flowering of literature in which attorneys defending the common law . . . thoughtfully examined their role, and that of judges, in the existing legal system. The vision of the common law they articulated in these writings was probably shaped in part by their experience as practitioners. Because litigators tend to focus on the facts of particular cases and on the flexibility of legal rules, they may have been particularly inclined to reject the conceptual formalism embodied by both complete codification and Langdellian classicism . . . .”
Grossman p. 200 (from same section): “At times . . . a controversy arises in the world of legal practice that requires members of the bar systematically to analyze the overall nature of the system within which they work. The codification dispute of the late nineteenth century was such a moment. And the resulting portrait of the common law painted by these lawyer-jurists was resoundingly different from that offered by Christopher Columbus Langdell. Instead, the anticodifiers’ vision of the common law foreshadowed, by several decades, the views of the aggressively anti-Langdellian legal realists.”
Tamanaha p. 74: “This discussion will close with yet another demonstration that leading ‘formalist’ thinkers were not guilty as charged—in this context with holding to the view that precedent must be strictly adhered to no matter what. Adherents of historical jurisprudence [Tamanaha earlier discusses Carter as a ‘historical jurist’] did not typically consider precedents inviolate, for their view was that law was an ongoing social production.”
Grossman p. 184-85: “Carter acknowledged that the doctrine of stare decisis sometimes denied common law judges the flexibility they needed to keep the law in line with changing social norms. . . . Nevertheless, if Carter had adopted a stringent version of stare decisis, he would have undermined his own primary argument for the superiority of the common law over a code—namely, that the former, unlike the latter, was capable of resolving each case according to the dictates of justice. . . . Consequently, Carter whittled away the doctrine into insignificance.”
Implications of Anticodification
There’s an interesting difference between Tamanaha and me here. Tamanaha focuses on the “realism” of the proponents of codification. I explore the realist characteristics of the anticodifiers.
Tamanaha p. 47: “[R]ealistic attitudes about law and judging were by no means the invention of the legal realists. Realistic observations can be found wherever there are critics of law or critics of judging, and the codification debate had both.”
Grossman p. 151-52 (from introduction): “This Article . . . suggest[s] that at least some late-nineteenth century jurists so devalued formal conceptual order, at least when it came into conflict with case-specific justice, that they can hardly be characterized as ‘classical’ at all. The anticodifiers, most notably James Coolidge Carter, their leading intellectual voice, explicitly minimized the role of formality and conceptual order in common law decision making. . . . Indeed, in trumpeting the advantages of the common law, Carter, an almost exact contemporary of Langdell, manifested a rule skepticism that foreshadowed that of the legal realists a half century later.”
Both Tamanaha and I end our articles with critiques of the strict periodization of American legal history (including the portrait of a “formalist age”) by Llewellyn, Gilmore, Horwitz, Kennedy, and other scholars. Our proffered explanations for this phenomenon differ, however; I focus on general scholarly trends, including the rise of the Kuhnian paradigm-shifting model of intellectual history, whereas Tamanaha stresses the political motivations of leftist scholars “denigrat[ing] the vanquished opponents” of the welfare state.
Tamanaha also makes a more extreme overall claim than I do. As evidenced by the title of his piece, he wholly dismisses the standard story of late nineteenth-century formalism, calling it “a bogus tale.” My conclusion (p. 219) is a bit more modest:
I do not claim that James Coolidge Carter was himself the paradigmatic legal thinker of the Gilded Age. I do, however, reject the notion that Langdell’s brand of amoral legal science typified the period, and I also question the complete hegemony of “classicism” broadly defined. More generally, I intend my examination of the anticlassicism of the Gilded Age anticodifiers, and their commonalities with the realists, to promote a healthy wariness of sweeping characterizations of any era in American legal history.