In a country that consumes as many pigs as China does, it's difficult—maybe even impossible—to build and operate a pork reserve big enough that it can steer the gargantuan, national swine market by holding intermittent pig-sales or hog-grabs.
The pork reserve's two rounds of buying this year came in at 75,000 and 93,700 tons, respectively, combining to account for only 0.3 percent of the total Chinese market, according to Rabobank's Pan. Some analysts put the percentage even lower.
"It is not very effective, because the volume is too small," Pan said.
The precise size of China's pork reserve is a closely held secret, but what is known is that there are two types of hog on reserve: the kind that's alive, and the kind that's frozen. Some company-owned farms in China are designated as state reserve hog farms, but even those farms operate under a normal market mechanism.
"They will serve the government only when there is a need," Pan said. "They're scattered everywhere, in almost every province."
China introduced the frozen part of the hog reserve in 2008, after a particularly acute shortage. But freezing hog meat and holding it for when the market gets hungry is an iffy business, at best: Sources who spoke with CNBC put the cap on how long such meat will safely "keep" for consumption at anywhere from four to six months.
Pareles of the USMEF agreed that the strategic reserve doesn't possess the heft in terms of tons of pigs under its control in order to decisively move markets. He further pointed to the fact that the size and price of pig purchases "aren't announced until after the pork has been acquired."
Other pork subsidies, many of them offered by individual Chinese provinces and municipalities, sometimes undercut the effectiveness of the strategic hog reserve by bringing their own influences to bear on the market. Those can include subsidies per sow or per veterinary vaccine, for instance.
The central government's own efforts can get in the way, as well. As China tries to industrialize its hog production and bring it into the hands of fewer, larger entities, it has introduced subsidies that favor big producers over independent farmers, and big slaughter facilities over smaller ones. Such subsidies can, in turn, shape the market more than the pork reserve itself.
"Many Chinese industry analysts think that the reserve's ability to significantly control prices is waning," Pareles said.
—By CNBC's Ted Kemp
Correction: This story originally misstated the amount of pork shipped from the US to China in the first quarter of this year.