When he proposed a sweeping ban that would forbid restaurants in the city from offering foods which contain trans fats, New York City Health Commissioner Thomas Frieden said replacing the fat would be easy. But soon after the American Heart Association condemned his plan, Frieden softened his stance considerably.

At a breakfast forum last week, Frieden said: “The transition difficulty — getting from here to there — that, I think, is real. I do think that there are transition difficulties for some places.” No kidding. The Associated Press reported:

For mammoth fast food chains, compliance with the ban not only means finding that perfect blend in the lab but also involves overhauling its supply processes and changing menus throughout the entire company, which is “kind of like turning around a large army,” Frieden said.

The restaurant industry, of course, is already in mid-turn. Just because it may not be happening according to a timetable set by food police activist groups doesn’t mean it isn’t happening. Taco Bell, for example, just bid adios to using the fat in most of its products.

Letting individual businesses make their own market-driven decisions about when to start and when to stop offering products is the surest way to make sure changes are reasoned and panic-free. Chief trans fat scaremongers Walter Willett and the Center for Science in the Public Interest both played a role in getting consumers and restaurants to switch to trans fat in the first place. We only wish they’d remember history before insisting on repeating it.