Robert Wood Johnson Clinical Scholar Charlene Wong, MD, interviews law professor Timothy Jost about the Affordable Care Act's strengths and insufficiencies. He points out that one of the least appreciated future problems of the health insurance exchanges is "reconciliation." Jost, a nationally renowned authority on the legal points of the health reform law, explained that people who work multiple part-time jobs or move from job to job can't reliably predict what their annual income will be -- a key element used in determining how high a health insurance tax subsidy they qualify for. If their early guess gives them a larger subsidy than their later income justifies, they will have to pay the money back -- or have it deducted from their annual income tax refund. "This will come as a huge shock" to a lot of people said Jost, a professor at Washington and Lee University who regularly writes for the Health Affairs Blog.