By Michael McAuliff mike.mcauliff@huffingtonpost.com

"WASHINGTON -- The co-creator of the concept that Rep. Paul Ryan (R-Wis.) is relying upon to reform Medicare no longer thinks it will work. Henry Aaron, now of the Brookings Institution, got the chance to tell Ryan exactly why at a recent Capitol Hill hearing.

Aaron and former Urban Institute president Robert Reischauer came up with the idea of "premium support" in 1995, after the failure of then-First Lady Hillary Clinton's bid to reform the health care system.

The basic idea is simple: let people pick their health insurers in the private market, subsidize the premiums, and competition will drive down costs. That's the theory behind Ryan's plan, recently endorsed by Sen. Ron Wyden (D-Ore.) in a white paper the two wrote.

It differs from Aaron's original vision -- in part because it has fewer protections for beneficiaries -- but the essential concept is the same. Aaron said this isn't the time to test it out.

"In the years since Bob Reischauer and I put this Idea forward, I've changed my mind," Aaron said at a hearing of the House Ways and Means Committee last week--------------------------------------------------------------------

Ryan, chairman of the House Budget Committee, did not engage Aaron in debate at last week's hearing, instead relying on one of Aaron's Brookings Institution colleagues, former White House Office of Management and Budget head Alice Rivlin to argue why premium support can work. (She said she believes strict oversight and risk adjustment can be done.) Ryan's office did not answer a request for comment".