This study explores the challenges associated with light post-editing (LPE) in translation practice and training. It first reviews existing definitions and guidelines for both full and light post-editing, alongside previous research on the difficulties posed by LPE. Building on this foundation, three rounds of small-scale experiments were conducted within an action research framework to generate empirical insights and inform pedagogical recommendations. The findings highlight fundamental differences between full and light post-editing, revealing that transitioning to LPE remains highly challenging and that vague guidelines hinder students from consistently meeting its requirements. The study highlights the need for targeted interventions, such as clearer guidelines and gradual transition planning, when opting for light post-editing training. It also argues that, given LPE’s reliance on outdated assumptions, the rigid ‘light versus full’ dichotomy should be replaced with a more flexible, context-driven approach.