In the history of Hungarian Orthodoxy (and /or Ultra-Orthodoxy), the name Akiba Joseph Schlesinger (c. 1838-1922) is well known. He is credited with virtually creating a 'cult' of the Chasam Sofer. His father-in-law had been a student of the CS. He saw himself as following in the line and as totally faithful to the teachings and legacy of the CS (who died when he was only a year old).
He published a buch called Lev ha-Ivri (Lemberg, 1865), which includes the text of the Chasam Sofer's Last Will & Testament, along with a commentary. Although in his preface he writes that the work contains only the CS's teachings, one wonders how a short text (the Will) became a 330 page text if it truly contains none of Schlesinger's own ideas. But I digress.
After a discussion about how terrible it is that works of Torah content are being published in his generation by wicked people, there is the following interesting note on pg. 92 (text below)regarding "one of our contemporaries who wrote notes on the Talmud - all soulful people should not study Torah from it, because I know those who asked Rabbenu z"l why he would write to this individual with praises for him in the text of his responsa, and he told them a secret: this person has one foot chasing after Aher**, and if he didn't keep him close he too would join the assembly of the wicked with his scholarship - God forbid - and who knows what the end was? Therefore he put in efforts to draw him close.
Schlesinger is speaking here of none other than 'the Mahritz Chiyos,' ie, Maharatz Chajes (R. Tzvi Hirsch Chajes [1805-1855]) whose Talmud commentary (published first in 1850) is printed in practically every Talmud edition today. Accessible, if not essential, reading on him is the Ph. D. thesis of Bruriah Hutner link. Paranthetically, my impression of doctoral work is that generally the student is attracted to the topic, if not admiring. Hutner (David) must have been attracted to her subject, but ultimately he repels her, too, and this attitude predominates. I just found that interesting.
Oh, and is his charge true? Did the Chasam Sofer really write him in a respectful, praising manner only to keep him within the good group? In my opinion: maybe.
* The versions I am reading are that of Hebrewbooks.org - 1868 - and Otzar Ha-chochma - 1870. Apparently there are differences between the first and other editions. For example, in the first addition the acronym RMD is not fully explicated to mean "Rasha Moshe Mendelssohn." In later editions, M is even changed to read "Moritz." (Info courtesy of Meir Hildesheimer's exhaustive articles on the attitude of the Chasam Sofer and his disciples toward secular study, and his attitude toward Mendelssohn [in PAAJR]).
** Aher= 'Aharon Choriner Rabbiner,' ie, proto-Reform rabbi Aaron Chorin.