The author (who coined the term "premium support") specifically states that Ryan's use of the term "premium support" is unfounded and basically wants to turn Medicare into a voucher program which shifts the burden of healthcare to the elderly.

http://healthpolicyandreform.nejm.org/?p=14134Although the Ryan–Rivlin and House Budget Committee plans are called “premium support,” they actually jettison all or most of the consumer protections that distinguish premium support from bare vouchers. Both would shift costs to Medicare enrollees. The CBO estimates that by 2030 the House Budget Committee plan would increase the out-of-pocket share of health care spending for a typical Medicare beneficiary from the current 25-to-30% range to 68%. By 2050, the House plan would cut federal health care spending by approximately two thirds.4 Both plans would place substantial administrative burdens on the most vulnerable and infirm of Medicare’s enrollees. And both would surrender the considerable leverage that Medicare can bring to bear on providers to reduce spending and improve quality, which to date has gone largely unused but which the ACA aims to mobilize with the backing of the Independent Payment Advisory Board.
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In brief, current proposals are not premium support as Reischauer and I used the term. In addition, I now believe that even with the protections we set forth, vouchers have serious shortcomings. Only systemic health care reform holds out real promise of slowing the growth of Medicare spending. Predicted savings from vouchers or premium support are speculative. Cost shifting to the elderly, disabled, and poor and to states is not. Medicare’s size confers power, so far largely untapped, that no private plan can match to promote the systemic change that can improve quality and reduce cost. The advantages of choice in health care relate less to choice of insurance plan than to choice of provider, which traditional Medicare now provides and which many private plans restrict as a management tool. Finally, the success of premium support depends on sustained and rigorous regulation of plan offerings and marketing that the current Congress shows no disposition to establish and maintain.