Gerhardsson's thesis came under severe criticism including the constant criticism that he was guilty of projecting post-135 AD views on tradition back in to the pre-70 AD period, esp. in the criticisms of Morton Smith and Jacob Neusner. And yet Gerhardsson never claimed that the rabbinic methods in toto could be traced back to before 70 AD, he always distguished materials about education from the Tannaitic and Amoraic periods, and regarded Rabbi Akiba as a definite marker in a period of transition concerning rabbinic education. His point was that Akiba did not invent memorization and some rabbinic education techniques go back to an earlier period. This is confirmed by the language of "delivering" and "receiving" traditions as stated in the New Testament itself (e.g. Mk. 7.13, 1 Cor. 11.2, 23; 15.2-3). What is interesting is that Jacob Neusner wrote the foreword to the 1998 edition of Gerhardsson's book and basically apologized for his initial review of Gerhardsson which was too reliant on Smith's dismissive essay and did not take into account Gerhardsson's nuancing of his position. On top of that Martin Hengel, Gerd Theissen, and Richard Bauckham have all found in Gerhardsson's theory a genuine analogy with the transmission of the Jesus tradition. Rainer Riesner and Samuel Byrskog have also developed and furthered Gerhardsson's thesis in subsequent publications demonstrating the robustness of his approach. That is not to say that no legitimate criticisms remain valid (e.g. how does memorization account for the diverse details in the tradition and Jesus was more of an eschatological prophet than a rabbi), but critics have been unkindly dismissive of Gerhardsson's view of the traditon.
For those who want to read more see my WTJ article.