The avowedly reformist administration of President Pieter W. Botha has sown confusion in recent weeks by seeming to alternate between acts of repression and attempts at concession.

Underscoring an apparent inconsistency or uncertainty was the decision this week to spare the black squatter settlement of Crossroads near Cape Town from forced relocation just one week after the bloody repression of demonstrations there. These actions, which were paralleled by offers to talk to political foes, were followed by a crackdown on political dissent.

After carefully nurturing an image of change and reform during the past several months, the Botha government had appeared to backslide into what Afrikaners call kragdadigheid, or forcefulness, when police fired on the Crossroads demonstrators, knocked on doors in the middle of the night to search homes and offices, and detained key black opposition leaders.

The deaths of 18 persons and injuries to 234 at Crossroads, only to be followed by a rollback of the orders to remove squatters that led to the rioting, is but the tip of much more fundmental questions about the government's intentions.

At the core of current South African political life is its treatment of its political foes. Three weeks ago Botha offered to release Nelson Mandela, imprisoned leader of the outlawed African National Congress, if he would renounce the use of guerrilla violence.

The offer followed an invitation by Botha to all black opposition groups to join the government in new discussions about the country's future and seemed to indicate a willingness to negotiate with the ANC, which was banned and driven underground in 1960.

But last week, security police raided the top leadership of the main black opposition organization still allowed to operate, the United Democratic Front. Fifteen leaders are charged with high treason and are scheduled to appear at what many here say will be a show trial due to begin March 29.

Yesterday, in a gesture more in keeping with its original offers of talks, the administration released a white member of the ANC, Dennis Goldberg, who was imprisoned with Mandela 21 years ago.

Some observers believe these contradictions are the result of confusion as an administration long used to oppressive tactics tries to reform. Others think they expose the administration as insincere.

"I don't think they really know where they're at," said Helen Suzman, a veteran opposition member of Parliament. "They are not working according to any proper plan, and when things go wrong, their instinctive reaction is not to appear weak."

The government's explanation, expressed in conversations and at press briefings, is that there is a high risk of instability during a period of reform, and attempts at subversion must be put down firmly.

But even moderate black leaders such as Zulu Chief Gatsha Buthelezi and Nobel laureate Desmond M. Tutu regard the changes, aimed at reformulating the segregationist system known as apartheid and not scrapping it, as unacceptable.

Botha has said that maintaining white political control and denying the 21-million black African majority a role in the central Parliament are nonnegotiable, although he seems prepared to allow blacks more of a say at the regional level and more control over ethnic affairs.

Opposition leaders risk becoming targets of government action to crush what is perceived as a campaign by black radicals to sabotage the reforms for the purpose of fostering revolution.

Some of the government's hesitancy and backsliding also stem from the fear of a growing backlash among Afrikaner supporters, many of whom see the reforms as dangerous tampering with the apartheid system that could lead to eventual black control of the country.

The backlash is worst in populous Transvaal Province, and some Cabinet ministers from there seem to be trying to put a brake on the reform process. Frederik W. de Klerk, Transvaal leader of the ruling National Party, last week delayed the scrapping of laws prohibiting interracial sex and marriage, which Botha first raised four years ago, by referring the issue back to a new parliamentary commission after another commission spent 14 months discussing it.

Minister of Law and Order Louis le Grange, also from Transvaal, seems to be using his control over the police to offset any impression that the party is going soft.

A month ago Botha acknowledged the permanence of black people in the 87 percent of South Africa reserved for whites. The acknowledgment cut across one of the original tenets of apartheid ideology, which is that all blacks eventually should live in 10 small tribal "homelands," leaving whites to rule unchallenged in the rest of the country.

Botha still sees blacks exercising their political rights mainly through the "homelands," but his acceptance that some of them are permanently in white South Africa is forcing him to make ancillary concessions.

Two weeks ago Constitutional Affairs Minister Chris Heunis appeared to announce a major concession when he seemed to say that 44 business zones in the country's main cities would be opened for multiracial trading. On closer scrutiny by opposition members of Parliament, the only change was that Heunis could apply to a special committee that fixes racial zoning to consider opening particular areas among the 44 he named.

"It was made to sound good, but it turned out to be pathetically little," remarked liberal legislator Tiaan van der Merwe.

On Monday Gerrit N. Viljoen, the government minister in charge of black affairs, announced that blacks who have qualified for the right to live in white cities under the strict influx-control regulations would have greater mobility. He said a new law would be passed giving these blacks the right to live in cities other than the one where they are qualified to work.

The tough qualifications remain that a black person must have been born in a city, or worked there for 10 years for the same employer, or worked 15 years for different employers, to stay in an urban area.

Viljoen raised expectations a month ago when he said the government was considering a reform of the influx-control system, which applies only to blacks and results in more than 1,000 prosecutions daily. Sheena Duncan, head of a women's civil rights organization called the Black Sash that specializes in forced removal and influx-control issues, described the concession as a "crushing disappointment."