“competition in the current system is too local, because it is centered on relatively small, self-contained local institutions catering to local needs. Services are both delivered locally and managed locally. The local bias in health care is a throwback to an earlier era when medical care was less complicated, and travel more difficult. It has been institutionalized by prevailing ownership and governance structures for provider institutions, regulatory and reimbursement practices, and a lack of local provider accountability for performance.”