Thus the SARB has little influence on the external value of the Rand. The repo rate as set by the SARB also, in my understanding, has little influence on the "carry trade" that SA relies so heavily on to finance the twin deficits. That is influenced more by bond rates and private lending, where the rates are determined by the perceived risk.

In protecting the internal buying power of the rand, i.e. controlling inflation, the SARB's inflation targeting has little effect. Due to the monopolistic nature of the SA economy (specifically in the government sector and soe's)  inflation is not really driven by demand, but by cost. No government agency like local government entities, water boards, ACSA, Transnet (goods transport and harbour fees), and especially Eskom have kept their increases anywhere near inflation. This increased costs for industry and forced increases in prices, even when demand did not justify them. The repo rate had no effect here on these prices. Cont..