In the first writing Interlude, under the section "Examples from the Published Literature," we quote William Darby and Jack Dubois's negative assessment of the treatment of music in Scarface (1932).
Here's another:
The Virginian, released by Paramount in 1929, typically features orchestral fanfares during the opening and closing credits and then uses strictly sourced music throughout its other portions. While characters whistle and even sing, and a traditional tune ("Bury Me Not on the Lone Prairie") serves as a rudimentary motive for the death of Steve (Richard Arlen), the erstwhile friend whom the protagonist (Gary Cooper) must hang, there are large gaps -- trail drives, romantic interludes, a final gunfight -- that seem strange because they lack the dramatic musical support to which modern audiences have become accustomed. (p. 9)
From this, you can see the basis for their lack of sympathy with the sound tracks in many early films: their aesthetic priorities are clearly those of the mature Hollywood sound film, with a bias toward dramatic underscoring.
Darby and Dubois also write a large number of short descriptive essays on individual films. Some of these run to several pages and could serve as the stepping-off point for an analysis exercise, project, or comparison/criticism paper. (Their book is American Film Music: Major Composers, Techniques, and Trends, 1915-1990.)
