Dollars have the disadvantage that they can only be coarsely targetted. A timely, laser focused argument will always beat whatever keywords Kellyanne Conway hap

Dollars have the disadvantage that they can only be coarsely targetted. A timely, laser focused argument will always beat whatever keywords Kellyanne Conway happens to be spamming millions of viewers with today. Campaigns at that scale just can't scratch the same itch. The trouble is laser targetted arguments take much more time to formulate, so you have to use them sparingly. The tau comes in handy.