Where the line height is 1.5em, the power of persuasion is at play.
Adjust font size to 20px to see the real power of the typographic regime.
But be warned, at 20px, the text may become too persuasive.
For the love of all that is good and holy, do not attempt to adjust the line height to 1px. The people will revolt.
Or, if you must, you can try, but do not say we didn't warn you.