I don't know if you've noticed this, but there are academic books and dissertations that are so bloated with inessential material that there is little left for the substance. About a year ago I wrote a book review of a 279 page book about the work of 3 Argentine poets.* You would expect that you would learn a lot about these three poets, but in the end you don't. Everything is so laborious in setting up the context, that we don't have a poem cited until page 80 or so. With so much contextualization, we might think that we would know a lot about the poets' lives, or have something concrete to grasp about their approach to poetry, but we really don't. We don't get interesting commentary on the poetry, just a lot of "according to so-and-so..."
I call this dissertationitis, or inflammation of the dissertation. Students learn to do research and acquire knowledge, but not to catch themselves in the act of coming up with an interesting idea, realizing why it is interesting, and developing it. Instead, it is about being very thorough and showing all the work that has gone into it, with little concern for the reader's attention. There is Theory, but it isn't well integrated.
In a book of similar length, I could do more with the work of 5 or 6 poets. In fact, I have. Ezra Pound has something in the ABC of Reading about works that don't contain much information on each page. Literary criticism should be condensed, as Pound argued poetry should be. We know the dichtung = condensare etymology is not valid, but the idea behind it is.
*I've changed some details here to disguise the identity of the book and author, etc... so when I say poets it might be dramatists, etc...