Novices should learn more about how the doubling cube works. Most intermediate and some advanced players will see a big jump in their game by being more aggressive and doubling when they have a "material advantage" and especially if there's a "gammon possibility."
My DG friend was correct. Within a few months, I saw my rating increase by almost 200 points! The cube can help you lock in the 1 point for sure, or double the value when you have the advantage.
More technical details on the doubling cube are beyond the scope of this blog -- but here's a great article with more details about the doubling cube.