Miller was a Lecturer in English Philology at Oriel College and Brasenose College in Oxford in 1953-57. During his time in Oxford, Miller, became also one of J.R.R. Tolkien's B.Litt. (Bachelor of Literature or Bachelor of Letters) students (starting on January 20, 1952). During four years he worked on his thesis on the Middle English fabliau (comic bourgeois tale) Dame Sirith, examined by Tolkien and G.V Smithers on March 2, 1956.