Final answer:
The sentence implies that the writer is overwhelmed by criticism and is selective about which criticisms they respond to.
Step-by-step explanation:
The sentence 'If I sought to answer all the criticisms that cross my desk, my secretaries would have little time for anything other than such correspondence in the course of the day, and I would have no time for constructive work.' implies that the writer is overwhelmed by criticism and that if they were to respond to every criticism, it would consume their entire day, leaving no time for productive work. This suggests that the writer is selective about which criticisms they respond to.