One round of highlighting is almost worthless on its own. BUT. "Progressive summarization" (term coined by Tiago Forte) starts with broad highlighting, followed

One round of highlighting is almost worthless on its own. BUT. "Progressive summarization" (term coined by Tiago Forte) starts with broad highlighting, followed by 1-2 more rounds of increasingly refined highlighting, and finally rewriting material in own words based on the last round of highlights. Leads to deeper understanding and recall etc.