I had Alan for first semester Lit Hum.
First off: Alan is completely brilliant, and knows all of the Lit Hum readings inside and out--not only in English, but in Latin and Greek as well. This allows him to convey unique and interesting insights into everything from the Iliad to the Bible. Also, he always spends a part of class explaining useful Greek/Latin words and concepts, which adds a lot to the overall understanding of the course. That being said, Alan is a misanthropic personality who allows his apathy to spill over into the classroom.
With his knowledge, experience, and love of Greek literature, Alan could easily be one of the best Lit Hum professors at Columbia if he wanted to. Instead, he chooses to show movies (which is fun, but ultimately a waste of time), discourage students from coming to office hours, rant about the uselessness of the Core, and ask students difficult existential questions before refuting or mocking their answers. When we read the Bible, Alan made a habit of calling out inconsistencies in the stories and doctrine. This in itself was understandable, but he would also force the one self-identified Christian in the class to explain and defend contradictions that even a theology student might have had trouble understanding. This got to the point where it seemed like he was wasting class time just to try and "logic" her out of her religion, an activity that benefitted no one.
If the point of Lit Hum is to turn Panglossian freshmen into cynics who suffer existential crises about the inevitability of death and can reference Euripides at the drop of a hat, then Alan succeeds admirably in his job. He pushes students to think about difficult topics and to question whether their deepest beliefs are blind dogma or legitimate ideologies. In the process, however, he dismisses students' ideas and creates an environment in which the potential hazards of speaking up greatly outweigh any benefits.
At the end of the semester, you WILL leave Alan's class having fully discussed, read, and analyzed the texts and broader thematic elements of the course. You will have a deeper understanding of some of the greatest literature in history and, as cliché as this sounds, yourself. However, you will probably leave with an underwhelming grade, a new-found fear of voicing your opinions, and a hollow pit in your stomach that reminds you that, as Alan says, "life it just the painful progression of mortality."