Usually, when people speak to different people, they choose to use different speech patterns. These different patterns usually reflect maturity, respect, familiarity, etc. So the way that I would speak to my grandparents would be greatly different from the way I speak with my classmates in university. These patterns of speech are broadly called Registers.
Now, Chaucer was supposed to be good at writing in different registers, evidenced by his ability to compose the speeches of his characters in the Canterbury Tales, who come from different backgrounds, and therefore different speech patterns.
Apparently, for my Chaucer midterm, it was questioned whether I was doing the same thing by using a sciencey register. I used "scientific" words -- words that I felt were succinct and poignant. What were these words? "fractal", "macroscopic", "entropy". There might have been one or two more, but those were the big ones.
I won't argue that if these three words were given in a row, most people would conclude that these words were drawn from a science vocabulary, instead of a literary one. But the allure of using scientific words is their objectivity. It *fits* what I need to say in a single part of speech without having to resort to adverbial and prepositional phrases. But perhaps that would be preferred for some profs, in order to preserve the illusion of a literary analysis.
Of course, these things rest on a continuum, and I'm pretty sure that my semi-scientific answer to the midterm wasn't far in the extreme. Just, perhaps, a bit more than the average English major. But when a novel or poem addresses things like the nature of time, it's extremely difficult for me to avoid resorting to the rich register developed to describe exactly that -- Time. Physics comes in handy for this, to talk about time dilation, and quantum singularities, etc. Sure, it detracts from the poetic image of that "tumultuous invisible river", but it is still a clean approach.
Which apparently was the second issue -- that the scientific approach was more distant than what most English majors would be(?) I wasn't really sure what he was trying to say. Maybe that the objective perspective isn't always the way to approach literature, or that I wouldn't be fully experiencing literature by maintaining my objectivity. No answers, but I enjoy the criticism; it gives me more things to think about and explore [through my essays which are weighing more and more as the term progresses].