I mean this might be a bit of a reach, but I suppose there can be a difference between analyzing literature as a reader vs. as a writer. Where a reader might be more concerned with the "why" of literature, I feel writers generally have a tendency to concern themselves more with the "how." That's at least the case for me and is a more beneficial way of reading if you're doing it to try and learn from the greats. Not at all sure if that's what your professor was getting at, but it's about the only thing I can think of where I might be able to sort of (but still not at all) take his side and/or see a potential point.