Yes, I truly wish the Geography Police will go away.
Like you, I have noticed that many "correct" South African place names will cause searches to fail. Also, the drop-down facility that is supposed to help you select correct place names is totally dysfunctional.
I might observe that all records from the Western Cape Archives in Cape Town and the NGK Archives in Stellenbosch are filed by the LDS under "Cape Province, South Africa". Even those before 1700, never mind 1910. Searching for some made-up place like "Dutch Cape Colony" will get you nothing. And, please don't get me started on the Germany vs. Holy Roman Empire topic!
It would actually be useful, I think, if those who wish to do geography rather than genealogy would make a table that cross-references place names by date. And then make the place drop-down function minimally intelligent by having it look at the date (of birth, for example) when it suggests alternate place names.
My Meintjes ancestors were trekboers, it seems, from day one. The progenitor was in the Koue Bokkeveld (Ceres), his children in the Roggeveld (Sutherland) and then the Agter Sneeuberg long before 1800. The place was Rietvallei, which is the west bank of the Fish River at Cradock. It is interesting to read accounts of how they "moved" from Stellenbosch to Paarl, Tulbach (not Tulbagh), Roodezand, then Graaff-Reinet (and perhaps Swellendam). Those places are the parishes where their baptisms and marriages were recorded, not the places where they were living.
Keith