Conventional wisdom suggests that a sensible politician will not tie his own hands. How often have we watched a political leader twisting and turning to avoid making a commitment to which he can later be held? If politics is the art of the possible, why shrink the boundaries of possibility in advance?

In the recent past, however, President Cyril Ramaphosa has deliberately circumscribed his own future freedom of choice. This apparently curious strategy has now begun to pay political dividends.

First, in the campaign for the ANC presidency, Ramaphosa ran a respectful race against his adversary, Nkosazana Dlamini-Zuma. He refused to campaign on the basis of her weaknesses, or the problematic relationship she was widely assumed to have retained with then state president Jacob Zuma. In retrospect, we can see how easily bridges might have been burned if Ramaphosa had exploited the obvious weaknesses in Dlamini-Zuma’s record.

Ramaphosa’s past restraint has enabled him to enjoy a positive relationship with Dlamini-Zuma today. This has undercut claims that the ANC would inevitably split over the December Nasrec outcome. Ramaphosa also enjoys a high degree of flexibility when it comes to the appointment of a deputy state president in the absence of the expected nominee, David Mabuza.

In a second precommitment, Ramaphosa embraced the controversial ANC resolution at Nasrec in support of expropriation without compensation. There were plenty of good reasons to drag his heels or to equivocate, among them proliferating land invasions and nervous international investors.

By unfailingly supporting an explicit right on the part of the state to effect expropriation of land without compensation, Ramaphosa went into national elections undercutting the EFF’s more radical plans to nationalise all SA land. Now the president can manage changes to government policy in a less politically charged environment.

Third, Ramaphosa committed himself last February to reduce the size of the cabinet and undertake a streamlining of the machinery of government. At the time this appeared to be an eccentric decision. After all, as Jacob Zuma demonstrated so amply, adding additional cabinet members and deputy ministers provides a convenient way of dispensing patronage to potential adversaries and buying off discontent.

Now that the election is won, however, Ramaphosa’s precommitment has suddenly become a powerful weapon to wield against his adversaries. Rather than being faced with a tortuous set of negotiations about who is to sit on which chairs around a very large cabinet table, Ramaphosa has the perfect pretext to remove politically inconvenient comrades altogether. Given the strength of his promise to downsize, indeed, he is more or less obliged to undertake a drastic cull.

The binding character of this obligation has now encouraged a number of problematic senior comrades – Malusi Gigaba, Nomvula Mokonyane and Baleka Mbete among them – to jump ship in advance of what had become their almost inevitable exclusion.

Finally, Ramaphosa placed corruption in his own party at the centre of the election campaign. Talking tough about the issue, Ramaphosa repeatedly pledged that action would be taken, and that misdemeanours would not be swept under the carpet.

Continuing a narrative that helped him narrowly secure the ANC presidency in December 2017, Ramaphosa presented himself as the leader of the “good ANC”, intent on uprooting the “bad ANC” that had taken charge in the Zuma years.

Given the absence of any early progress in corruption investigations, and the presence in government of many of those implicated, Ramaphosa was asking voters to take a big gamble on him – and on the ANC. It is in the nature of his precommitment to reform that he simply cannot shift towards politically expedient cabinet appointments over the course of this weekend.

The strategy of binding oneself in the future is counterintuitive for most politicians, and they have often viewed Ramaphosa’s precommitments as strategic blunders. However, as every good constitutional negotiator knows, appropriate precommitments can sometimes be the very essence of political power.

• Butler teaches public policy at the University of Cape Town.