[Aiwendil]

for example, I have no idea what a LitHum class would be

Sorry, it seems that certain jargon is a bit too firmly embedded in my head. "LitHum" or "Literature Humanities" is the required freshman western literature survey class here.

I’m curious… In what context would you mention Tolkien in the average college literature lecture or class discussion?

Tolkien came up in my class as a result of some general and fairly abstract discussion of the 'purpose' or nature of literature. The prevailing opinion was the somewhat modernist view that literature is essentially ironic; the author writes a,b,c and means x,y,z. I argued, using Tolkien as an example, that 'heroic' or non-ironic literature is just as valid - that is, a,b,c means a,b,c; it is not code for some other message or argument. Not that I think this is somehow a necessary or even natural discussion in which Tolkien must be used - it's just an example of how he came up in my class.

In what historic or critical literary category would mention of Tolkien’s work be most beneficial?

I'm not sure what you mean by 'beneficial'. In terms of medieval studies or any similar class, of course Tolkien's fiction would be quite useless. But surely not all literature classes merely use literature as a tool for the study of society. A good deal of literature is studied for itself. There are classes on James Joyce that endeavour to examine Joyce's work, not to use it in some way to illuminate another area of study.