Popper's Ratchet and the No-Ad-Hoc Rule

This week Bruce puts Popper on trial. Specifically, through the lens of Michael Stevens’s book, The Knowledge Machine, which argues that science works because it follows the “iron law of explanation” where scientists must (at least in public) put aside philosophy, politics, and theology and only follow empirical evidence. Bruce asks, how compatible is this view with the epistemology of Karl Popper?And does Strevens' critique of Popper ring true? Or is it a strawman?