President Obama and some members of Congress assert that, in cutting Medicare and Medicaid, they can whack healthcare providers while protecting beneficiaries. But experts say it is not so simple. Experience, they say, shows that some cuts in payments to providers hurt beneficiaries, as more doctors refuse to take Medicaid patients or limit the number of new Medicare patients they will accept. Hospitals curtail services. Beneficiaries may have more difficulty getting therapy services after a stroke, traumatic brain injury or hip fracture.