Barack Obama famously and falsely said, “If you like your doctor, you will be able to keep your doctor, period.” But . . . what if you don’t like your doctor?

Let’s say you, like me, are one of the 20 million Americans who work for themselves—no boss, but also no corporate-tax deduction for health insurance. The smart move is to get a high-deductible insurance plan. Now it suddenly matters what doctors charge: $500 to take your blood pressure and bang your knee with a rubber hammer, $1,200 for a blood test that uses pennies...