Aim: The main aim of this commentary was to connect the insights from the contributions of the special issue on the intersection between depth and the regulation of strategy use. The seven contributions in this special issue stem from three perspectives: self-regulated learning (SRL), model of domain learning (MDL), or the student approaches to learning (SAL). Procedure: Prior to combining insights from different studies, the definition and operationalization of cognitive and metacognitive processing in the seven contributions is described. Subsequently, the grain size and statistical methods used in these contributions are discussed. This information allows us to--albeit cautiously--combine the results from the different studies regarding the relation between cognitive and metacognitive processing. Conclusion: Deep processing and self-regulation/monitoring showed a strong correlation, regardless of the theoretical framework or data collection method chosen. The strength of the correlation between surface processing and metacognitive processing differed, however, between the studies. Pathways for future research on students' cognitive and metacognitive processing are suggested, at the methodological level as well as regarding the conceptualization of unregulated learning and surface processing.