In an interview on Fox News  last month, Treasury Secretary Steve Mnuchin made a sales pitch for the  GOP’s tax reform plan—specifically, its plan to cut corporate taxes.  “Most economists believe that over 70 percent of corporate taxes are  paid for by the workers,” he said. His implication, in laymen’s terms: Regular workers would get 70 percent of the benefit of corporate tax cuts. Five years ago, the Obama-era Treasury department found the exact opposite