You need to be able to hold facts in your own working memory while you think about them. If you do this with the same facts, and think through different combinations, they’ll stick in your memory for longer.

I never sat down to memorise trivia about the Roman calendar, but I know Julius Caesar was assassinated on the 15th, the ides of March, because of repeated exposure while thinking things through.

It seems like old assessment techniques could luck in to testing comprehension, because the people who understood things would also remember them. This devolved into the recall being seen as the goal, instead of as proxy measure of something harder to test.