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The word "unexpectedly" for negative economic reports has become a much-mocked cliché in the media over the past five-plus years of recovery, but this week's final look at first-quarter economic growth deserves an exception. First estimated at a meager 0.1 percent annualized rate, and then downwardly revised to -1.0 percent in May, most economists expected a smaller revision to the downside – in the -1.5 percent-1.8 percent range. Instead, the Bureau of Economic Analysis calculated the drop as -2.9 percent, a full three percentage points lower than its initial estimate, and the worst quarter since the technical recovery began in June 2009. Read More Obamacare's problem: You can't fix stupid—Op-ed

Almost immediately, the Obama administration and its apologists began insisting that the sharp decline meant nothing. Cold weather caused it, some claimed, even though the US has had cold winters in the past without suffering undue economic damage. In fact, this was the worst Q1 read on GDP in 32 years (1982), and the three winters following that produced annualized growth rates of 5.3 percent, 8.2 percent, and 4.0 percent. This was hardly the first tough winter America has faced in terms of weather, but it was the worst in decades economically.

The owner of Bardenay in Idaho, Kevin Settles, had to put expansion on hold – and the new revenues and jobs it would create – while tracking employee hours and setting up health-insurance options for those who worked enough hours to qualify. He even offered to get more of them insured if they worked at least 39 hours a week – and was shocked when only a handful accepted. Others quit to work at higher-paying part-time jobs. "To my surprise, having had this program in place for nearly a year," Settles told The Post, "I don't think the staff cares that much" about health-insurance coverage. Businesses care about it, though, especially the cost. Investors' Business Daily has documented over 400 mid- to large-sized employers that will or have already cut worker hours to avoid the full-time classification that will force them to provide health insurance or pay fines for non-compliance. Not all of these are private-sector employers, either. The list recently added seven public school districts that intend to cut hours for non-teaching personnel, moves that will save them millions of dollars in benefit costs. The Post also reports a move by French food-service company Sodexo to reclassify 3,000 workers as part time in order to drop their health benefits. Read More Obamacare subsidies could hurt at tax time

Evidence is mounting that the practice has become widespread even among companies that don't announce their intentions. When asked about this rational response to incentives, White House economists suggested watching payroll data to see whether distribution of part-time hours remained steady or shifted as the mandate approached, and last year published a study claiming no effect had been seen. However, the study relied on a method of rounding up that made workers averaging 29.5 hours (which does not qualify as full time for the ACA) to 30 hours (the threshold for full-time designation in the ACA). In reality, the numbers of workers getting 30-34 hours of work a week has dropped 6.4 percent since the end of 2012, while those getting 25-29 hours a week has risen 10.8 percent.