With a view to better preparing teachers to engage in linguistically responsive feedback practices, we examined what 120 preservice secondary English language arts teachers (PSETs) considered to be “useful” and “appropriate” feedback to English learner (EL) writers by analyzing posts to an online database of student writing and teacher feedback. Findings of this qualitative study show that PSETs valued linguistic diversity, shared many core orientations of linguistically responsive teaching, and sought to give ELs holistic writing feedback; however, they ultimately equated useful feedback with error correction. PSETs were highly attuned to EL errors, but they were not able to connect different types of errors to language development and could not determine which errors were appropriate to correct given the student’s proficiency level. Furthermore, PSETs largely ignored ELA content and attributed appropriate EL feedback to teacher bilingualism rather than recognizing the need to learn about ELs’ interests and backgrounds. We suggest equipping PSETs with skills to learn about ELs and leveraging extant PSET attention to grammar with additional knowledge of language development processes. Identifying proficiency-level-appropriate errors could allow PSETs to selectively correct errors and provide space for more substantive feedback on ELA content.