well, i went to the public opening!
its even better than the images.
the answer about the structural strength relates to the fact that all the vertical tubes are already joined together and so hold each other up. the ones that were partly cut away got a reinforcing coating of extra concrete in their inner surfaces which can be discerned having a slightly darker tone.

there is a room filled with an installation designed by Liza Lou american artist who gets her huge beadwork creations done by the members of a bead working project who are based in South Africa, near Durban, so -another reason to support the museum!

anyone who goes to Cape Town should also make sure to visit the traditional/ethnic/colonial national history museums where beadwork and some other items of real importance and rarity are displayed and very thoroughly catalogued.