One important point on the issue of a roundabout is the part about giving way to traffic approaching from the right – ” he or she shall yield right of way to traffic approaching from the right, within the roundabout,” This is a little further down the page on Arrive Alive and is the wording as contained in the law.

Slow down and give way to other vehicles that cross any Yield line before you do.
Proceed in a clockwise direction around the painted island, without driving on it.

They also have this to say about roundabouts:

- As you enter the roundabout, traffic coming from your right has right of way. This means that traffic streaming into the roundabout from the entrance to your right will keep coming as long as no one is coming from their right.
- These cars may not even slow down as they enter the roundabout, because they have the right of way. You must stop and wait until there is a break in traffic. Watch out for other traffic in the roundabout.

It’s all here, http://www.arrivealive.co.za/pages.aspx?i=2163

Another point to note is that in a roundabout you give way to traffic approaching from the right, and here is the important part, within the circle. Not approaching the circle.

So please learn the rules.
See http://www.circles.org.za for clarification.