Marc B. Shapiro writes circa 1992:
Hildesheimer came down firmly on the side of Orthodoxy. In his mind, Frankel, Graetz, and other professors at Breslau were heretics. Not only was Frankel a meshumad—which made him even worse than an apikores—but it was perhaps even a mitzva to burn his book Darkhe haMishna.16 Hildesheimer had the same view regarding the graduates of Frankel’s seminary.17 This harsh view was broadly shared among the German Orthodox. Yet as time went on, some elements of German Orthodoxy were able to take a more balanced look at both Frankel and his work. With this change, certain segments of Orthodoxy, especially the Berlin variety, began to adopt a more sympathetic approach to Frankel and the sort of scholarship he represented.18 Horovitz adopted a more positive attitude than his teacher Hildesheimer. In referring to Frankel, he prefaced his name with the compliments usually reserved for Orthodox scholars.19 However, he did very conspicuously neglect to add the customary “of blessed.memory” after his name; a fact which did not go unnoticed.20
Hoffmann makes good use of Frankel’s works. Whether this is a sign of a positive attitude to Frankel is not certain for Hoffmann’s practice was to quote anyone without concern for their religious beliefs. He recognized that good scholarship cannot limit its choice of sources or neglect proper historical methodology.21 Thus, whether Hoffmann held the same view of Frankel that Hildesheimer did cannot be definitely established. Even a close examination of Hoffmann’s writings will not settle the question for he was always very respectful in what he wrote, even when confronting those who denied the very basis of what to him was holy.22 However, the general impression one gets from the way he approaches Frankel’s works is that Hoffmann, much like Horovitz, had a positive, or at the very least neutral, opinion of Frankel.
With Weinberg, we see more than we have seen so far. For him, not only was Frankel not a heretic, he was actually a good Jew. Weinberg calls him Rabbi and on occasion affixes the phrase zikhrono livrakha after his name; a sure sign of respect, and one that is notably missing when Weinberg mentions Geiger.23 Fie cites the Darkhe haMishna throughout his works and considers this book to be a basic text and a forerunner for Floffmann’s later studies of the Mishna. He also defends Frankel against Isaac FHalevy’s harsh attacks throughout the latter’s Dorot haRishonim attacks in the spirit of Hildesheimer.
