He refers to this Op-Ed (Stop Coddling the Super-Rich) by Warren Buffet: http://www.nytimes.com/2011/08/15/opinion/stop-coddling-the-...
Personally, I think that Daniel Indiviglio's arguments against taxing this investment money are flawed.
In both cases he is arguing against double taxation. He says that corporations are taxed before they pay dividends, so therefore dividends shouldn't be taxed again. It seems that payroll taxes would also qualify for this logic. As for double taxation on income, sales taxes, tolls, and fuel taxes are similar. There's plenty of places where corporations and earners are taxed more than once. Therefore, I don't see it as a strong argument why these investments should be any exception. Even so, Buffet is not suggesting a new tax, only an increase in an existing one for the highest earners. His argument is a red herring. The dividend tax exists. Buffet is not arguing for its creation, just an increase in the rate. Also, Buffet is suggesting raising the tax rate only on annual income over $1M.