It would be easy to test that fact on an exam, and students would feel comfortable memorizing that fact. But the real insight lies in the process that made Jupiter massive. Until we understand the concept of the solar nebula hypothesis and the processes by which the inner and outer planets grew, the large mass of Jupiter is just an isolated fact. Once we understand the concept, the mass of Jupiter fits into a bigger picture. It not only makes sense, but it is easy to remember without memorization.
Understanding is always a more robust form of learning than memorization.
In my course, I have avoided introducing facts unless they are needed to explain astronomical phenomena. Moreover, I have focused discussions to show students how astronomers use facts as clues to new hypotheses and as evidence to test existing hypotheses. Of course, we need facts as grist for the mill of scientific inquiry, but we should not make the facts an end unto themselves. Our goal is understanding nature rather than remembering facts. There are no Oscars for college courses, but teachers of introductory astronomy can take heart that they would be big winners if there were.