Related Clues:

• Work on proofs, say
• Emulate Maxwell Perkins
• Correct copy
• Mark one's words, in a way
• Correct errata
• Change, as text
• Worked on a Life sentence?
• Trimmed text
• Rewrite a bit
• Work cutting words
• Use a 21-Across, e.g.
• Fix some paragraphs
• Mark one's words?
• Make revisions to
• Toil over text