But mostly it's just private surfing on office time - nice if it's part of your core duties, not so nice if it's not.

I don't see how doing online research related to one's job can be construed as being "private surfing on office time".
The Internet is not just for sending and receiving business-related emails - it is thanks to Telkodemonopolies that {some..many} South Africans have allowed themselves to be boxed into the bad mentality that the Internet is a time-waster, rather think of search engines like Google being a productivity tool, which, when used properly can save a lot of time.
/me huggles my smoothie
Allows up to 5 different adsl accounts, and it's easy to switch between them without any hassles.
Yep, [searchforum]Smoothwall[/searchforum].org or its derivative [searchforum]IPCop[/searchforum].org

.
This guy should have done a little more research before posting this article. He seems to have expected Telkom to switch between his 3 Telkom accounts for him (when they get capped). This is impossible unless Telkom hacks into his router.
What he probably wanted to purchase, was 3GB top-ups, something Telkom doesn't offer (which I think it should offer).
I think you missed the point of the article in your 1st paragraph, and then hit on the point in your 2nd paragraph:
the problem is essentially that TelkodemonopoliesHindernet is a crap ADSL-ISP.
TelkodemonopoliesHindernet forces customers into using multiple ADSL ISP Accounts instead of offering either a data-allowance-topup or higher cap accounts.
Also worth noting that TelkodemonopoliesHindernet does not offer uncapped ADSL ISP accounts, whereas many other ADSL ISPs do offer uncapped...
IMO TelkodemonopoliesHindernet fails to compete - simply bcos it believes it doesn't have to compete - it is still a large part of the monopoly on ADSL in SA, so there is no incentive to improve and make thing easier and more efficient for customers.
ADSL in SA is far from perfect, but one can pick one's poison - I choose to stay far away from the deadly poison that is TelkodemonopoliesHindernet.