The law of unintended consequences endlessly reveals itself in public policymaking, particularly in areas where it is most market distorting. Mandating the purchase of insurance was the solution to healthcare free riders, 12-ounce maximum soft drinks (the proposed solution to obesity), and now a federally mandated purchase of 4 gallons of fuel is the solution to preventing damage to small engines from blender pumps serving E15 gasoline. Apparently E15 causes premature engine failure in motorcycles, and enough residual fuel remains in the pump hose that dialing a machine back to E10 would still introduce the risk of damage to the vehicle. The rule from U.S. Environmental Protection Agency (EPA) will force motorcyclists, lawn mowing equipme...