Usually those anatomy-of-a-rumor stories are left to high-level political machinations. But now, for once, there's a rumor that can come directly into our kitchens.

The background:

Two years ago a company named Nikkal Industries -- Japanese name, Virginia Beach location -- sent forth to the marketplace a new idea. This idea, developed with a combination of Japanese and American technological and marketing expertise, was the Donvier ice cream maker. It was an immediate commercial and critical success, because it worked. (It still works.)

The Donvier people thought of something the rest of us should have thought of long ago. Their ice cream maker operates without the help of salt or ice cubes, nor does it use electricity.

Instead it uses a refrigerant, sealed into the bottom and sides of a metal cylinder. You put the cylinder in the freezer overnight, then pour in the unfrozen ice cream mixture. The refrigerant freezes the ice cream. All you have to do is turn a handle every few minutes. As in other ice cream makers, the handle turns a paddle that removes the frozen ice cream from the sides and rotates it to the middle. This both helps the ice cream freeze evenly and keeps it from becoming grainy.

This handle-paddle business is the source of our rumors.

Those who used the Donvier at its beginnings noticed a certain wobbliness in the handle as it turned the paddle. Not a major wobbliness, certainly, and not enough to detract from the fact that this was that rarest of happenings in the marketplace -- a truly new, truly good idea.

And the Donvier sold like hotcakes despite this minor worry. For the first time, home cooks could whip up a batch of real ice cream on a whim, using neither the energy of electricity nor much of their own.

In fact, the blade often did break. Donvier promptly replaced the broken blades, but urged customers to follow their instruction booklet more carefully. Customers, the company found, let too much time elapse between turns of the handle. The ice cream then had a chance to freeze hard around the edges of the cylinder, with the result that the paddle would break with the effort of trying to budge the hard-frozen stuff.

But a few months ago the word began to circulate in kitchen equipment circles that parts of the machine had been redesigned and that the troublesome parts were now stronger. Store personnel vouched for the improvement. One friend, a longtime ice cream cook who had looked at the original machine and decided against buying it because of this seeming instability, took a look at the redesigned machines and changed her mind.

The hitch in this story is that, while certain cosmetic changes were made by Donvier, the new machine is structurally identical to the old one.

Then why does everybody, from retail store personnel to potential buyers, think it's changed? "We keep hearing that too," says Anna Creery of Donvier.

The Donvier people speculate this way:

Right after Christmas, their free consumer telephone lines lit up like -- well, like a Christmas tree. Donvier got so many calls that they had to hire extra workers just to answer the phones.

Apparently every second person in the United States got an ice cream maker for Christmas, and lots of them were having trouble with their paddles. (Freezers run colder in the winter, which makes the cylinder colder and the ice cream mixture freeze harder and faster.)

At the time the company was already consulting with its Japanese technological experts about the paddle problem. They tested a variety of new designs and materials and concluded that they couldn't improve on what they already had. What was required, they decided, was some kind of educational program encouraging customers to follow instructions more carefully.

Meanwhile, everybody who called the consumer line was told that the company was testing new ideas. This "everybody" included store representatives, who may have multiplied that information by relaying it to customers. Like the old birthday party game, what came out at the end was not necessarily what was said in the beginning.

As for why potential customers who never heard about the phantom improvement would declare the machine better now, it's just possible that the cosmetic redesign made the machine look sleeker and therefore stronger.

In any case there is no reason to distrust the company's conclusion that it had the best structural design in the first place. Its responsiveness to consumer complaints has been fastidious, including a willingness to replace broken paddles immediately, even if the customer abused the machine. And, having come up with a truly winning idea and marketing it at a fair price, it isn't about to give away the goose that laid the golden egg.