Subject matter experts who design workplace training frequently overestimate what learners can absorb at once, creating cognitive overload that undermines learning outcomes. Their deep knowledge of a topic makes it difficult for them to remember what it felt like to be a beginner, a phenomenon cognitive scientists call the "curse of knowledge."
When experts build training, they pack material with technical details, jargon, and complex connections that feel obvious to them but confuse novices. They skip foundational steps they no longer consciously think about. The result: learners struggle to process too much information at once, working memory becomes taxed, and retention drops.
Cognitive load theory, developed by psychologist John Sweller, explains why this happens. The human brain can hold only a limited amount of new information simultaneously, roughly four to seven distinct pieces. When training exceeds this threshold, learners cannot build mental models or transfer knowledge to new situations.
Learning and development professionals can address this by inserting themselves between experts and learners. They should ask experts to identify core concepts first, then strip away peripheral details. Breaking content into smaller modules helps. Sequencing matters too: foundational knowledge should precede advanced topics.
Another strategy involves having experts teach novices directly and observe where confusion happens. These "struggle points" reveal where the curse of knowledge is strongest. Experts often assume a step is obvious when learners need explicit instruction.
Testing assumptions through small-scale pilots catches these gaps before rolling out training at scale. When subject matter experts see actual learner performance data, they better grasp what's missing from their mental model of how beginners learn.
The fix requires collaboration. Subject matter experts bring accuracy and depth. Learning designers bring pedagogical skill. Together, they can craft training that respects both content quality and cognitive limits.