I've said this before, but I couldn't disagree more. In my experience, you can't get a sense of Apartheid-era South Africa, what's changed, and what hasn't, without visiting Pretoria, the Voortrekker Monument, the Apartheid Museum, the Hector Pietersen Museum, downtown Johannesburg, the northern suburbs, the Saxon Hotel, etc. It's like asking if you should only visit San Francisco or maybe squeeze in one day for Washington, DC & New York too.
David