Johannesburg — The South African government's strategy to coopt some blacks into the ''system'' has suffered a major setback. On a still, summery Saturday, blacks in Soweto - South Africa's largest black settlement - gathered on doorsteps, watched children play street soccer, or joined the weekend shopping rush into nearby ''white'' Johannesburg.
But very few Sowetans - about 11 percent of those eligible - voted in the Dec. 3 elections meant to give them more control and responsibility for administering the poor, strictly segregated and politically restive community in which they live.
The poll was only nominally higher than the 6 percent that voted for a slightly different form of local government in 1978, and regarded then by analysts as a strong rebuff to the white government.
Soweto's rejection, along with that of most all the other 28 or so black townships that have gone to the polls since November, blunts the latest thrust of the white government's policy of so-called ''reform.''
Pretoria is attempting to ''stabilize'' urban black communities to avoid the kind of unrest and violence that erupted in Soweto during 1976. This is essential for the economy, which is increasingly reliant on skilled black labor, and for the credibility of South Africa's public relations campaign to convince the world it is sincere about ''reform.''
But at the same time, Pretoria is developing strategies to ensure that these relatively privileged urban communities are strictly controlled in terms of size and distribution so that they do not represent a threat to white rule.
It appears the major reason blacks boycotted the local elections is that they were perceived as an integral part of Pretoria's policy of ''reform,'' which blacks reject. Indeed, the government has made clear that local government for blacks is not a step towards central government participation, but rather away from it.
During its recent successful referendum campaign on the issue of bringing coloreds (persons of mixed race descent) and Indians into the white Parliament, Pretoria affirmed to whites that it was not a step toward inclusion of the black majority as well. The government said blacks were embarked on a ''different route.''
That route calls for blacks to have political rights only in the tribal ''homelands.'' Blacks reject the policy.
So far Pretoria has emphasized the ''carrot'' side of its new program for urban blacks. These township elections were seen by the white government as a major concession. In legislation passed earlier this year some black townships like Soweto have been given expanded authority to rule themselves, albeit within the confines of apartheid. The current round of elections was to establish town councils under the new legislation.
The elections came against a backdrop of other concessions. Since the riots of 1976, the government has been upgrading the physical environment in which urban blacks live, although it remains far inferior to that enjoyed by whites. In Soweto, for instance, new schools have been built, new roads laid, and an electrification program is expected to be completed sometime next year. The government also is selling off homes to blacks.
But black frustration has not lessened and blacks are waiting with some skepticism to see what ''price'' they must pay for these concessions.
The government has hinted at the ''stick'' side of its program for urban blacks. Legislation introduced at the same time as that for expanded local government - the so-called Orderly Movement and Settlement of Black Persons Bill - would have restricted even further the number of blacks permitted to come to the cities and enjoy the limited rights available there.
That legislation was temporarily withdrawn. But analysts expect similar legislation designed to the same end to be passed soon by the government, perhaps in the next session of Parliament.