מנקר לי במח - בעקבות יתושו של טיטוס

For those who don't know, Duenner's approach anticipated that of Halivni in some respects, primarily in the assumption that the answers given by the amoraim, while binding for halakhic purposes, are not necessarily the best explanation of the Mishnah. Duenner also pointed to a couple of passages in the Talmud — both of which are in the current daf yomi tractate — which he believed are interpolations from the heretics, intended to mock the rabbis. He claimed that the rabbis would never have discussed the case of one who falls off a roof and while landing on a woman has sex with her (a highly improbable scenario, to put it mildly), or that a holy sage would come into a new town and announce that he was looking for a wife for the night (Yevamot 37b, 54a). According to Duenner, these texts are the product of those intending to mock the rabbis, and were unfortunately taken by later scholars as authentic.

Breuer's grandfather, Rabbi S. Z. Breuer, was one of the leading opponents of Duenner, going so far as to threaten to place him into herem if he didn't stop publishing his hiddushim, and put the ones already in print into genizah. Duenner refused, and the threat of a herem was never carried out. His hiddushim were later reprinted by Mossad ha-Rav Kook, and some unpublished material was also included in this new edition.