This is old, but I recently learned of it.
A couple comments:
Hamilton is my favorite Founding Father. Idealistic revolutionaries, charismatic leaders, and military geniuses are a dime a dozen, but a person who can handle government finances well, and design good economic and political institutions, is much rarer. If you look at the history of our country, the thing that really sets us apart is the strength of our financial system. New countries usually crash and burn because of money issues, but Hamilton's policies helped us avoid that fate.
The guy who raps this is a very experienced performer, a veteran of literally a thousand Broadway shows. And yet, his song introduction is full of vocalized pauses and he comes across as a nervous, stammering novice to public speaking. The fact that he was performing for the President of the United States probably had something to do with it. It shows how anyone can choke in a high-pressure situation. But once he got going with the rap, he was fine. That shows the importance of practice and experience.