As ChatGPT is increasingly used in second language (L2) writing practice and research, its potential to provide feedback and revision has attracted much scholarly attention. However, it remains largely unknown whether and how ChatGPT revision can influence rhetorical move-steps. This study investigates the effects of ChatGPT revision on rhetorical move-steps in English personal statements (PSs) written by L2 English undergraduate students, using a combination of corpus data and stimulated recall interviews. Based on an unstructured prompt, our analysis revealed significant reductions in the rhetorical efforts devoted to five rhetorical steps. Students’ responses highlighted both benefits and concerns regarding these revisions, illustrating how AI-generated changes can alter textual features and affect writer-reader communication from the writers’ perspective. The findings highlight the importance of students’ critical evaluation of AI-generated revisions and iterative engagement with them.