I can't really answer your question because all of your premises are wrong. Your concern about the IRS is irrelevant: they enforce policy, they do not define it. Your concern about Congress is also irrelevant, since this change can be made through a different process.

The quote from the Secretary of the Treasury did answer the nature of your concern. She has been on reserve boards for almost 30 years, and is head of the department that is concerned with all financial matters in regards to the federal government. If that's not good enough, I'm not sure what would be satisfactory for you.